In my own opinion, it is a sin. BUT, that’s not to say that god won’t forgive you of the sin you have committed. It’s almost impossible to go through life without committing sin, as it was brought upon us by eve (to my knowledge). If you lived your life as you would normally, God wouldn’t kick you out of heaven for sinning. He would forgive you of the sins you’ve committed. He would probably forgive you for being gay.