Does he like me??

Ok so I am 17 years old and there is this guy in one of my classes that I really like and for a while he was getting super close with me and he would do thing that showed me that he liked me but I wasn’t sure because I’ve never had anyone show me those kinds of feeling so I was wondering if he actually did like me... the biggest problem though is that he has a girlfriend and lately they’ve been getting in a bunch of fights and the girlfriend of the guy that I like doesn’t like me because the guy that I like tried making his girlfriend jealous with me.. so does he like me or is he just pretending to to get back at his girlfriend