SZM, your problem is not that you don't know how to study, or what and when to study, your problem is that you are afraid to take risks.
More than 300 posts, and you still haven't identified the loophole.
It's not your problem alone. It's everybody's problem. Just that some people have learned to overcome it. Something you still need to do.
Take the time you need to realize it. As Angel said, confidence. Confidence is in you, not on SF or anywhere else. You just have to find it in you.
And you will only see it when you will not be blinded by worry.
Just stop worrying unnecessarily. If you keep a big heavy metal load tied to your legs, and keep dragging it all the way, you won't move far. And in life, you need to go as far as you can. You need to live. Every day. Every second. You need to make the most of it. You need to start believing in yourself. You need to start making your own decisions and you need to learn to stick to them. Sometimes, there will be people to guide you. But most of the time, you will have to walk all alone. Sometimes even, people will try to use your weaknesses to misguide you. You need to be able to sieve through good and bad. For that, you first need to trust yourself.
I will not write the same thing over and over again. When you are reading this, read it as an SZM who knows exactly what she wants in life-- and how to get it.