So I've been wondering lately how I am able to figure out who is gay/bi. I'm sure there's hints and things here and there, but right now I don't know anybody IRL that is gay/bi. I want someone else haha, I'm lonely! But yeah, are there ways to tell with other people?
I've been wondering the same thing, but I find that I myself show no outward signs of being gay. I listen to the same music everyone else listens to. I watch the same movies and read the same books. I have the same hairstyle and clothing choices that any straight girl would have. So honestly, I think there's no "real" way to tell if someone is gay/bi/straight. I mean, some guys may be more flamboyant and obvious about it. And some girls may chop their hair off and dress more masculine in a way that's become stereotypical of lesbians. But in this day and age, the only way to know for sure is to ask somebody.
Probably the best way to tell is by paying attention to someone's eyes while in a conversation. For instance, if you're having lunch with someone and you notice his eyes drifting toward an attractive waiter as he passes by, that could be a pretty good indicator.
There's plenty of ways to meet people - you can go to local LGBT meetups or other social activities, for example. That might be a little hard at your age (a lot of them are targeted towards adults), but it's definitely a possibility. Then there's the obvious option if your school has a GSA, I'm sure you'd meet other gay/bi guys there. Other than meeting people at places that are gay targeted or where gays are known to congregate, there's really no easy way to tell. If you met me on the street, you wouldn't think that I was gay at all.