I’m not sure if my crush is gay

So basically I’m in this youth group (which isn’t religious) and there’s this one guy who is really cute. Last year was my first year in this group and so I didn’t know him that well. Over the year we got to know each other more and we became somewhat close. He does not go to my school but his best friend does and we would have lunch together last year every other day I then cane out to him and he said that he won’t tell anyone. That same day he went back home and for some reason has the urge to walk all the way over the his best friend’s house (who is my crush) and tell him that I’m gay with no explanation. About a few weeks later I asked this friend if I should come out to him and since he felt guilty about telling him he said yes and went over to him and told him that I was gonna come out to him and told him to act surprised.

Fast forward to September we had this seminar in thing in a house we rented. The boys all slept upstairs in the same room and there was no door to the bathroom so basically anyone who showered was seen. So tbh at this point I couldn’t give less of a **** if any of them saw me naked so I went in to take a shower and he was there and saw me naked and told me that I’m big and what not. Which made me so uncomfortable. Turns out his best friend also thinks he’s gay because he never talks about girls and when he asks him if he’s gay he goes “what? me? no” but in a suspicious way. Whenever we talk he’s kind of flirty but I don’t want to be flirty back cuz I don’t want it to be awkward if he isn’t actually gay. What are tips to find out if he is gay?