what do i do ??? help!

I like this boy at my university. He’s very attractive and other girls also like him. He’s spoken to me a couple of times and has asked me to come up to him, he also has me on instagram and likes my posts and watches all my stories everyday. However, there’s another girl who likes him and he likes her posts and watches her stories but they don’t talk much.. this girl was also a bitch to me and tried to offend me by calling me the wrong pronouns on the university group chat. anyway, a friend of mine is having a get together and both the guy i like and the bitchy girl are invited and i don’t know what to do.. i’m so scared she’s gonna try to talk to him the whole night while i sit there like a lemon. what should i do??