So there's this girl I sit beside in my class, and she is really, really pretty. She's also really kind of mysterious, and is one grade below so she doesn't know anyone in the class. As soon as I saw her (2 ish months ago) I instantly started liking her. She's really cute, too, and always smiles but doesn't talk a lot. I haven't talked to her (ugh i hate myself for that) because I'm so quiet and shy around her, and normally she's playing a game on her phone, or listening to music. I don't know what to say to her... Also, idk if she's straight or not. I'm really scared that she'll end up being straight...
It's possible she's straight, but you won't know unless you talk to her. You say you're in a class together - maybe you could ask her about an assignment, or ask if she wants to study together. You could ask her what game she's playing on her phone, or something like that. Otherwise, I would suggest keeping your expectations in check. Like you say, you don't even know if she's attracted to women and comfortable with that. So, try talking a bit, see if you two manage to hang out, and if you do, if you'd feel comfortable coming out to her. That might be a good first hurdle to think about.
Just try to get to know her more. Start with small talk, ask basic questions. You'll eventually find out more about her.