Opinions/Advice on boys please

So I like a guy, he knows I like him because I told him. This guy likes another girl, and the girl knows I like him. Basically we all know who likes who except for the girl who won’t give a clear answer. Personally I don’t believe she likes him, I just think they’re really close. I have seen them text each other “ily” and a few other very slight flirts. She doesn’t have a confident answer and has even said things like I can have him. For clarification she isn’t mad that I like him, so it wasn’t just a rude comment, she was being genuine which surprised me. I have grown closer to this guy lately and the girl and I are somewhat friends. The guy really wants the girl to like him and is willing to do a lot, like try changing his personality. When he thought she didn’t like him he cried himself to sleep. As stated I really like the guy, so seeing him upset makes me upset. If you were the guy would you do? What should I do since this is hard on me due to not only liking him but not wanting to see him sad? I have tried getting him to realize he is perfect as is, but he doesn’t seem to listen. Is there anything I should say or do to help the situation? Also, we are all highschoolers!