Anyone has had the same feeling? Anyone has managed to overcome this and enjoy a life that was designated when you were born?
Realising I wasn't an Antarctic Explorer, army leader, crack scientist public speaker artisan breadmaker lego designer extraordinary was .. liberating.
What I did is work in the not for profit sector for the public interest and make small incremental improvements which give me some satisfaction. I'm not FAANG wealthy and I don't care. I get to switch off and watch TV. I like being ordinary.
30 is young. You have a long life ahead. Don't live it on coulda/shoulda/woulda for a goalset drawn from other people's public persona, which is very often inflated, and self aggrandisement and humblebragging. Find a role and do the best you can in it, to make the world a better place. If that's small scale effort take pride in it.
Have experiences while you can. The more the merrier. Do not neglect your health. Learn pedestrian things like how to cook, how to fix a car.
BTW "imposter syndrome" never dies. I'm 62, retiring inside 5 years after a lifetime in compsci and I still don't know what I want to be when I grow up.
For me it is kind of normal to skim through a manual or a documentation to understand what I'm working with. Nobody seems to do this. It made me outstanding in many cases, a true magician. I don't think I'm very smart, but I'm often refered to as "the expert".
At one point you suddenly realize everyone is just doing the bare minimum und tries to get through whatever project with the least amount of resistance. Their scope is usually what is in front of them and what they are working on. Basics are quickly forgotten and what you can set up in day puzzles others for months.
It is so easy to be useful, just stick to your ability and expand them slowly. Everything is a process and everyone is struggling at first. Accept this and try to help with much care. Just installing some driver, writing a parser for MS Excel or other things that seem so simple or redundant are of great help to others. You be amazed what little skill you need to be "the expert". Mostly passion, interest and embracing the struggle on your own feet.
There is no top of society. You can choose to be helpful or be a dick who orders people around and laughs at their misery, when they struggle with the simple things.
We all stress out so easily and the hurdles we need to overcome are extremely difficult, until they are somehow not. You won't believe it, some people struggle to set up some IDE for a few days and then produce the most amazing code.
Live in the space, where you can explain the obvious. For most the obvious can not be explained and you are an idiot for asking. The former makes you "the expert", the latter makes you unbearable.
If you have concrete answers to these question, try to get down to the essence of what they might mean. Once you know you can have a more concrete idea of what it is you actually _want_ (often it turns out it's not necessarily those things you think you want) and what steps you might be able to take to get there.
If you do have the means, I would also encourage you to seek out some psychological counseling. Not because you sound "sick" or in dire need of professional help but because it can be very beneficial to bounce ideas off, get some feedback from an impartial person and have a trained eye look at what you're dealing with.