How do I get a boy to like me

There’s this guy who I really like. I only have two classes with him but I had almost all of them last year. We don’t talk unless we get partnered, we sit on different sides of the room. He unadded me on snap the day he accidentally saw my bra (I had a crop top and it went up for like 1 minute and I didn’t notice ugh) what do I do??? My friends say to add him back and see if he adds me back and also tell him I like him but I’m socially awkward so I have no idea how to tell him.