Ok so there is this guy and he does a sport with me he starts
Half a hour after me and allways looks at me and my friend I think he likes me but I can not talk to him because his class goes on after mine I really like him what must I do

Nothing... school is far more important at this point... anything else will distract you from your studies.

Odds are 99.9999% no matter what you do a few years from now he will be a distant memory, but what happens with school and your grades now WILL effect the rest of your life most likely.