Hi, Ankit. I am sure you have done many great things in life. This pandemic is a tough time. We often feel depressed because we are in such a situation. This is normal and happens with everyone. Its good you decided to talk. First of all, start loving yourself the way you are and start appreciating yourself if nobody else is doing that for you. Nobody knows your struggle better than you yourself!
Also, its never too late. Especially for you! You are just 21 years old. Your life is just starting now.
Don't lose hope right at the beginning.
Don't compare yourself with anyone else. We all are beautiful in our own ways.
Coming to the your question, SBI conducts a number of exams throughout the year. The banking sector is always in high demand and so the competition is also high. Any exam is easily crackable if and only if you really want to crack it.
Take coaching classes, keep giving various exams by SBI (even if just for experience), work hard and there you are with the best rank possible.
Right now the first thing that you have to do is research about all the exams, posts, jobs by SBI and decide a goal. That "this is the particular exam I want to crack, this is the dream job I want and this is where I see myself in future".
Once you are done deciding your goal.
Start planning on to how you are going to achieve that goal. Then work on it and execute your plans.
Keep working, keep giving mock tests then.
I am sure you will crack it.
Once you are done deciding your goal, we can always help you with the information you need regarding your journey to fulfill your dream. We are always just one question away from you!
All the best!
And please smile, the more you think and feel good the more you attract good things in the universe (Law of Attraction, explained beautifully in the famous book- The Secret by Rhonda Byrne).
You are precious and capable of doing wonderful things in life.

Don't feel so low , Cheer up and s tart a new life.

See the Sbi exam is very easy to crack provided you study well . The syllabus consists of Logical Reasoning and most of it is Quantitative Aptitude. Start your preparation using the books of R.S Agarwal . It is the Best book for studying for all bank exams.

BE POSITIVE

See the link below for all details of bank exam:

https://competition.careers360.com/articles/sbi-careers

Thank you