There are a couple of ways we might think about the questions you're raising. One is by trying to look for an Archimedean Point, so to speak, that provides some sort of absolute or incontrovertible answer. The other way is to look at how we actually think about these sort of things -- look from the inside. Since I have no Archimedean point available to me, I'll offer the latter sort of response.

What we think does depend on what we've experienced, but even though my life is different from yours, we have lots of common ground to appeal to. Obvious sort of case: if you and I were both to look out my office window, then even though your experience is not just like mine, we'd agree that there's a building directly across from us. We'd also agree that there's a large grassy area behind it, and that there are people wandering around in the vicinity. Other cases of ho-hum agreement among people are more complicated, but we could multiply examples indefinitely.

We can also agree that some people are better positioned to have a view. If I look at an x-ray, my opinion about what I see isn't worth much. I know that, and so does anyone who knows that I have no medical training. But a radiologist can tell a lot. I'll defer to her opinion, and so should any sensible person in my position.

And on it goes. Our ordinary notions of evidence, reasoning and so on clearly can carry us a long way. Add the refinements of science and math and we get even further. By those lights, some people really are more justified in believing certain things than others, and we can come to reasonable consensus about who is who. Some of what "led you to being who you are today" was sound: soaking up the deliverances of your senses, thinking carefully about evidence, taking counsel from those who know more than you.

Two things, however. One is internal to the whole system. There are hard cases, and there may even be unresolvable cases -- from the point of view of our usual conceptions of evidence and reasoning. True though that may be, however, it doesn't undermine the fact that we know a lot, and that not everyone is equally expert on everything.

The other point may be closer to your worry. We could toss everything up in the air and become skeptics about all our usual beliefs and standards. We could do that, but the mere fact that it's possible doesn't give us much of a reason to. There's a larger point here. We can look at knowledge, belief, expertise, etc. notions that call for the sort of Archimedean perspective that we noted above and duly set aside. Some philosophers think that unless we can find such a point (and we can't), then skepticism is the only reasonable response. Most philosophers, for better or worse, think that that's a hopeless approach.

So in short: from the point of view of our usual standards and practices, we have all sorts of reasons to think that some opinions are better than others. If we toss all those standards and practices aside, we're radically adrift. But there's no compelling reason to give ourselves over to the currents.

It isn't right to say that Christianity, per se, advocates a god that values what you might call blind faith, i.e. faith which is not grounded in reasoned argument. Perhaps that's true of some sects, but certainly not all. Catholic tradition has it that the existence of God is rationally demonstrable (and that God wants us to use the reason that we have been endowed with). So those atheist critics who argue that the supposed arguments for God don't work -- whether purely a priori arguments or partially empirically based arguments -- aren't point-missing, but are directly engaging with a major strand of Christian thought which holds that there are rationally compelling arguments for his existence.

But suppose you do posit some god that goes out of its way to hide itself and give no rational evidence for its existence (even though it wants us to be credulous and believe in it). Then to be sure, the empirical state of the world is the same whether or not such a being exist. By hypothesis, we have no evidence, empirical or otherwise, that such a god exists. But then why on earth believe in it any more than in all the little green demons or the Flying Spaghetti Monster that equally hide themselves away? By hypothesis, there isn't the foggiest reason to believe in such things. So don't.

Initial disclaimer: I am no epistemologist. But I'm not sure I quite understand. First, why are all assumptions about basic beliefs, etc. dogmatic? Are you perhaps demanding that one must be certain of such things? Why isn't it good enough to say "I know Peter was at the meeting because I was there and I spoke with him?" People who say things like that could be mistaken, of course. But suppose that as the world turns out, I'm right: I did attend the meeting and I did speak with Peter. Then don't I know that he was there? If not, why not?

Perhaps the worry is that I don't know that I know this (doubtful in this case, but happens sometimes.) But it's long been doubted that knowing X requires knowing that you know X. Perhaps the thought is that to know X always requires being able to give some particular sort of justification. But reliabilists wouldn't buy that. On their view, I know something (roughly) if my beliefs about it come to be in a reliable way, even if I have no clue what the mechanism is.

So while certain sorts of projects in epistemology fail, the field is still thriving, near as I can tell. But in any case, it seems to me that one sensible version of the epistemological enterprise takes it for granted: we know lots and lots of stuff. The project isn't to prove this, but to provide plausible analyses and accounts of what this amounts to. Seems like a reasonable project to me.

I have a couple of comments.

First, let me commend you for your sincere interest in an important topic.

Second, beliefs that you are "scared into" are unlikely to last long-term. You are wise to be skeptical of such a process.

Third, you don't need to 'stop thinking', but your mom is correct that you should relax. This is not an issue that you are likely to get a quick resolution on.

Fourth, now for the really bad news. There is nothing resembling a consensus among philosophers on this issue. Many have thought God exists and it can be proven. Others have thought that the evidence is inconclusive, but that we should believe in God for either moral reasons (Immanuel Kant) or for prudential reasons (Blaise Pascal). Still others have thought that the evidence was inconclusive, so that we shouldn't believe. Yet, others have thought there was weight of evidence against belief in God. And finally, others have thought that all claims about God were inherently absurd.

I'd encourage you to take things slowly and talk to your friends, family, and religious leaders on the topic. You don't need to come to a final decision on one of the great philosophical debates at the age of 13. Eventually, I'd encourage you to read some great philosophers on this topic including Hume's Dialogues Concerning Natural Religion & Mackie's the Miracle of Theism (both against belief in God) and Richard Swinburne's The Existence of God & There is a God by Anthony Flew (both in favor of belief). However, I find most popular treatments of the issue to be pretty shallow.

For my part, I find that probabilistic versions of Aquinas's second argument for God's existence and Leibniz's cosmological argument are fairly convincing in favor of belief (both of which can be found via a google search).

I hope this helps.

You say: "if I stop thinking I'll, well, die"? This calls to mind that very famous idea from Descartes, "I think, therefore I am." What he means is that as long as I'm thinking, I must exist. What seems to worry you is the opposite--"If I don't think, I won't exist." But here's a very reassuring thing about Descartes' view. It doesn't matter what you think about. You can think about the existence of God or going swimming or eating ice cream, and the fact that you are thinking means you exist. In fact, what Descartes means by thinking is everything that goes on in your mind. So you can just enjoy the swimming and the ice cream, and that suffices for you to exist. In a relevant sense we even keep thinking in our sleep. Our minds are active. So closing your eyes at the end of the day isn't even anything to worry about.

Of course, some things urgently need to be thought about. And maybe it seems to you as though the question of God is really urgent. But is that so? If there is an all-good supreme being, I don't think it makes sense to think of him as punishing you for being an atheist or an agnostic, or rewarding you for being a theist. In each case, you come by your beliefs honestly, so what's to punish or reward? There's no reason to think your welfare turns on getting this sorted out. All the more reason to let yourself think about swimming and ice cream...and about religion only as much as you enjoy doing so.

It depends on your theory of knowledge, but several theories would support the idea that someone with ordinary cognitive capacities could actually know nothing. Obviously the most important such theory is the one known as "global skepticism," which holds that absolutely everyone knows nothing! We might have justified beliefs, even justified true beliefs, according to this theory, but never justified enough to qualify as knowledge.

Other theories might hold that a person would know nothing if that person's cognitive capacities were sufficiently damaged or defective. So a "reliabilist" about knowledge is one who thinks that we have knowledge only if we have a true belief that is generated or sustained in a way that reliably produced true beliefs. This obviously requires that the knower have the capacity to produce true beliefs reliably, so one who did not have such a capacity could never know anything (even if he or she might still sometimes have true beliefs). Obviously, this would have to be an extreme case of cognitive defect, however. Other cases, according to different theories, can be concocted, but most would be either rare or purely theoretical possibilities. Most theories of knowledge hold that all or nearly all of us (other than extremely defective cases) have plenty of knowledge.

I could come up with an argument that you don't exist, but it would be harder for you to. Descartes' point is that even in doubting that I exist, I seem to presuppose that I actually do. Descartes claimed that in any moment when I reflect on it, I know for sure that I exist.

That said, this shows much less than it might seem to. In particular, it doesn't show that there is any unified "self" that has a continued, coherent existence over time. The existence of that sort of "I" has been doubted by many thinkers, going back at least to the Buddha, but also, famously, by David Hume and more recently by Derek Parfit. Views of this sort are sometimes called "bundle theories" because they replace the idea of a unified self with a picture according to which we are an ever-changing bundle of sensations and thoughts.

Here's a link to the section of Hume's Treatise in which he sets forth his views on the self. Enjoy!

http://www.mnstate.edu/gracyk/courses/web%20publishing/TreatiseI.iv.vi.htm

It is a requirement for something to be genuinely known to be true that it is true. So knowledge implies truth (in the sense that if X knows that so-and-so, then it is the case that so-and-so).

But that doesn't make knowledge the same as truth. The implication the other way around doesn't hold. There are truths that you don't know, that I don't know, and indeed that no one right now knows (maybe because nobody has bothered to find them out, maybe because the time has past when anyone could check, or because the truths are about far-off events like meteorite strikes on the far side of the moon, or for other kinds of reason).

Leaving ominiscient deities out of it, not every truth is known. But we might wonder whether every truth is knowable, in principle, e.g. by a suitably placed and sufficiently smart observer. The trouble with that idea is in spelling out the "in principle".

It's worth saying something first about Descartes (as it wasn't his view that he couldn't prove he wasn't dreaming).

Descartes is troubled that, as he sees it, the then dominant systematic story of the world is in deep error, and is getting in the way of the growth of the revolutionary new science of the day. He has a diagnosis, too, of the source of error -- he sees Aristotelianism as springing from some deeply embedded childhood habits of thought. Radical measures are required to prise us out of such deep-rooted error. The ‘Method of Doubt’ provides the once-in-a-lifetime jolt needed to shift us out of certain childish thought-habits and to get us adopt better intellectual methods and open the way to improved science. Faced with even the most reasonable-seeming presumptions, Descartes suggests, "I must withhold my assent from these former beliefs just as carefully as I would from obvious falsehoods, if I want to discover any certainty in the sciences." So for Descartes, it is not that our former beliefs are all unreasonable: but rather we are to play along with fantasies about dreams and evil demons as an instrumental step to help us sort out the safe beliefs from the contaminated dross.

Descartes’s hope and belief is that, after a temporary strategic retreat from received views and common sense, he will still be left with enough indubitable foundational beliefs to provide a secure bridgehead from which he can fight back and recover those common-sense beliefs that don’t carry the baggage of disputable theory -- including of course his common-sense belief that he is sitting by the fire, wide awake. And he can then go on to ground a secure corpuscularian science.

Of course , notoriously, Descartes's fightback is problematic in all kinds of ways. But he certainly thought he could establish on firm grounds the general reliability of the senses and the security of our ordinary knowledge that we are not dreaming.

But that's history, you might say. Descartes might have raised the thought that he might be dreaming just as a methodological tool rather than as a hypothesis about how things really might be to be seriously entertained. But now the doubt has entered in, it (as it were) takes on a life of its own: so how do I prove I'm not dreaming?

Well, speaking for myself, I’m all for a cheerfully resolute response. We have every good reason to suppose that in ordinary life, when our usual criteria indicate that we are wide awake and not dreaming, we are wide awake and not dreaming. And what if the sceptic asks me how I rule out the possibility that, for all that, my whole ordinary ‘waking’ life is in fact just one big coherent dream (unlike any ordinary dream, of course, perhaps being a put-up job engineered by an evil demon)? I just riposte that I have been given not the slightest reason that to suppose that that is a live possibility. As the questioner puts it, it is difficult for me to take the suggestion seriously. Why should I? It is one thing to use the evil demon fantasy as Descartes does, as an imaginative tool in trying to locate some core of infallible beliefs: it is something else entirely to imagine that the honest enquirer needs to rule out the evil demon scenario before he can regard science (broadly conceived) as a reasonable enterprise. The scientist just doesn’t have to waste her time ruling out myriads of daft hypotheses she hasn’t the slightest reason to suppose are true. And for me, that’s pretty much the end of the story.

Of course, in saying that, I'm just relying on our familiar beliefs and best scientific methods for proceeding. But what else am I supposed to do? True, I can’t justify anything without appeal to such familiar beliefs and best scientific methods. But so what? Well, some say (in fact this is a quotation from Barry Stroud),

. . in philosophy we want to understand how any knowledge of an independent world is gained on any of the occasions on which knowledge of the world is gained through sense-perception. So, unlike . . . everyday cases, when we understand the particular case in the way we must understand it for philosophical purposes, we cannot appeal to some piece of knowledge we think we have already got about an independent world.

But what notion of ‘philosophy’ is in play here? I for one just haven’t much grip on what sort of coherent project there could be here, this special ‘philosophical’ enquiry that isn’t part of science broadly conceived. Again quoting Stroud, it seems that

All of my knowledge of the external world is supposed to have been brought into question in one fell swoop . . . I am to focus on my relation to the whole body of beliefs which I take to be knowledge of the external world and to ask, from ‘outside’ as it were . . . whether and how I know it . . .

But that gives the game away. If the ‘philosophical’ project is supposed to involve jumping outside my beliefs and methods, and trying to squint sideways at them from ‘outside’ as it were, to try to justify them as matching up to an external world, then that is just incoherent. If the sceptic is complaining that that project of justifying can’t be pulled off, then he’s quite right the project is impossible, but quite wrong to complain. You can’t be both ‘inside’ and ‘outside’ your own thoughts (thinking them, but squinting at them sideways too).

One thing I know is the difference between the taste of sangiovese and pinot nero -- a bit of wine-wisdom I've acquired over the years. But I certainly would be very hard put to express that knowledge in propositional form, at least in any informative way that could usefully convey my knowledge to you. Is there any proposition I could use to do that?

Of course, I can say -- taking a sip -- "this one is sangiovese", and -- taking another sip -- "that one is pinot nero". But that won't help you, unless you are sipping away from the same wines, and you are attending to the differences.

You need to experience the wines for yourself, and need to pay attention to them and learn to tell them apart. And developing that skill, that know-how, seems to require something other than picking up propositional knowledge-that about the wines.