should i ask for feedback?

I got rejected by a university today, which I really wanted to attend, I really wanted some feedback as to why my application was rejected. should I email and ask why this was the case or should I leave it .... really gutted but I will have to get over it...
if so how should I word it bc I don't want to sound passive aggressive...

Yes ask for feedback. Just explain that you were very disappointed to get the rejection and would appreciate any feedback they can give you on the reasons (make sure you have checked both ucas Track and any applicant portal first though - there’s often brief feedback there)