I read books, sometimes cried under stress, was not big or very good at sports, and stuck up for a friend in a ridiculous hypothetical (would you still be friends with someone if they had AIDS) and so obviously I was gay. This was 30 years ago when being gay was more synonymous with bad, to both kids and teachers, authority figures alike.
When I was young, this affected me by getting bullied and me spending a lot of time ashamed, alone and angry, though I still had friends in the other weirdos. As I grew up, I developed better social masking skills around manly men and the idiotic women who also internalized and weaponized those kind of gender norms. I now exclude a lot of people from my actual life and generally get along with women better than men.
I still carry baggage around. Recently one of my close female relatives was cheated on by her manly man husband. While I am mostly sad and frustrated for her and their kids, I'd be lying if I said I wasn't also mad for my own reasons. He's openly friendly, but inside he's the kind of misogynist asshole that told me I wasn't a man when I was younger. He was a cop too. Never trust a fucking cop.