How the crappers do you take care of an injured pigeon?

Just found an injured pigeon at school just now. Can't bring it to the vet cause it's too far. It can't fly cause it's wing is injured, can't really walk, when it does walk it topples back or forth and moves sideways. So honestly, how do you take care of an injured pigeon? do i bandage it's wings or something? what food do i get it since the pet store too is far away, and what medicine could i get? How do i take care of it at night? PLEASE HELP! Thank you!