IS IT BEST TO JUST STAY FRIENDS WITH THIS GUY?? THANKS:)!?

Yes, it's best for you to just stay friend's with this guy. He seems to be a bit childish (at 15....that's not surprising). He's just being a normal 15 year old boy. He likes you enough to want to stay friends with you which is a good sign so..... If you really like him, let him have his fun and stay friends. Wait until you both mature. Then you will see if you guys should be together. Have fun, don't waste your teen years stressing about stupid boys. You have plenty of time to find a good boyfriend and fall in love.