Crush on someone with a girlfriend

I recently became friends with this guy. We’ve gotten pretty close over the last couple months and we see each other daily. I’ve liked him since we met but he’s had a girlfriend for almost a year now. sometimes he does these things where i think he feels the same way like jokingly sit on me, put his hand on my leg, flirt with me, etc. but i ca t tell if he actually means it or it’s all in a joking way. I really don’t know what to do because it’s so hard to hide my feelings but he has a girlfriend and i don’t want to get in the way of that