You can like him but don't start dating him or seeing him alone. All those warning can come true. I know 10 year olds who've gotten pregnant. It happens to us girls because we don't take advice from those who've been there or seen it happen too often. A 16 year old boy shouldn't want to be with a 13 year old girl.
look at it this way in two years he will be 18 and you 15 even though 3 years isnt much think about this at that age youll both probably have the same thing on your minds and even at 18 ,15 will get you 20 that jail prison and lots of court in the middle depending on your parents and the local DA just a thought