Found: fantasy/shonen jump, strongest kid at his old school got kicked out because he went overboard.

this book isnt technically a book but a comic book thing on the internet that is about this boy who is new at this school and is 'totally powerless' but in reality has decided to go undercover and got expelled from his previous school because he went overboard even though he was the strongest and most respected. he is friends with one of the stronger kids at the school and the three strongest at the school bully him and so on. then later they push him slightly too far and he attacks them back and thankfully they had taken there quarrel away from the school and the rest of the students before railing him. in that fight you find out that his power is the power to take another person's power and throw it at them but far stronger. later his friend gets stuck with a needle that temporarily removes a persons power and he goes undercover again and basically beats the s*** out of the strongest students working his way up to the top.

Are you talking about people with different superpowers, people who all have superhuman strength, or just a bunch of normal humans who get into fights?

different superpowers.

I think it might be called unordinary https://www.webtoons.com/en/super-hero/unordinary/list?title_no=679&page=1 it sounds exactly what you're describing.

I can confirm you are definitely looking for Unordinary on WEBTOONS.

looking at it that is it. thank you.