How can I tell if he likes me and what do I do about it?

Okay so there's this guy I really like and we're both about 18. I've never had a boyfriend before and I don't have any brothers or male cousins so I have absolutely no prior experience in interpreting guys. We've gotten to be really good friends over the past few months. He told me he likes this girl and how he subtly asks her out (he told me her name too) but nothing ever happens. Lately I caught him looking at me a bit but I thought I was iver reacting. Then this weekend in a reply to a message I'd sent him he asked me what I was up to that night. I said nothing much. To which he said "if that's a regular occurrence maybe we need to get you out with me". Then I said "that would be heaps fun" and he has not replied (it's been about 24hrs). My question is: what's he most likely thinking/feeling and what does it all mean? And what should I do? I really like him and I know he's not a player. He is seriously the nicest guy so I don't think he's using me as a replacement for the other girl. But does he think of me as a friend, or does he like me? How can I get things moving here? Thank you so much!