I've often had an interest in pursuing outcomes that aren't exactly stable or risk-free, so I think I can relate to how you feel.
To make the most out of what you can do, make sure you understand what you can manage to do. Some people have to support themselves and genuinely can't afford to simply stop working (or going to school), because they need to survive. Others, on the other hand, can afford to maintain a ratio where they can work on their YouTube account more than maintain a job. Sometimes, they don't even need a job. Some choose to have a job, anyway, to make sure that they remain financially safe.
Some YouTubers are lucky enough to have very fast channel growth. Others -- and by others, I mean everyone else -- don't have that luck.
Assume that you won't be as lucky and genuinely do your best. If there's anything that you think is stopping you from doing so, see how you can fix that problem. Explore your options and search the forums to learn about anything that can helpful. Like you said,
there are absolutely no guarantees, so it's possible that you can try your absolute hardest for however many years you do this, and still not make it; should something worse happen to your account, you may not even have much to show for your effort. Would you be okay with that?
Besides that, I don't have much to add that everyone else didn't already say. Best of luck, and don't forget that you can also approach things safely when you need to. Don't underestimate what you can accomplish in short amounts of time.
P.S: Having support is nice, but remember that what you do is really up to you. You can make decisions that no one will agree with. Sometimes, you won't get the validation of others no matter what you do.
