ways to get through to a shy guy? *F15)

Hiii!!! So basically what the title says, but im going to provide back story cause maybe that will help!!

so basically, I (F15) have known this guy (M18) DON"T JUDGE MEEEEEEE for about 5 years and we're friends, but i wouldn't describe us as close. However, we do have good conversations occasionally but his body language is kinda odd. He;s always rubbing his hands, kinda sways a little (not like in a socially inept way, he just does idk) and kinda looks everywhere whether it be at more, or across the room or whatever.

Anyway, i also kinda wonder if he likes me back cause i followed him on insta, he followed me back. I followed his twin bro, which the bro permitted, but he didn't follow me back? And then on another app the guy i like and i are friends, but his bro will not accept my friend request and but hes friends with mutual friends. I don't get it. Does he maybe like me back and set aside boundaries for his bro or does his bro just not like me for some reason? But his bro is friendlier to me in person then he is... i'm so lost guys

anyway. ideas on how to get through to him and make him more comfortable would be great. I don't think age is really a concern cause 1) i dont think either of us are looking for a relationship rn, 2) we've known each other for awhile. 3) we're friends,

so yeah, thank you!!!