Give a girl advice

So my boyfriend and I have been dating for around two and a half years, and started having sex last summer (we were each other's first and all that jazz) and I don't know if i can have an orgasm or not. It's not just him either, it doesnt happen when I'm alone. Any tips/advice? (This is all unless I've already had one, but I'm pretty sure I would know if I had, but then again, I wouldnt really know what to expect lol)