on top of the advice others have given, i rly like their suggestions, sounds like you’ll have a gap to fill socially. i also struggled w friendships in public school and honestly if i could tell my past self something it would be that theres always a chance to change. i locked my self image in as the person who just struggled to make friends, and that somehow stopped me trying before i even started. it wasnt until later in senior year i relaxed and started to talk to people but by then it was nearly over lol. keep an eye out for clubs or sports that pique ur interest even if you dont think you’ll be any good. you have time to get good and its the easiest way to make friends. also dont be scared to talk to people in class even if its just about the assignment or something mundane. studies show the fastest way to friendship is proximity. its something i miss now that im an adult working from home :/ social situations are inherently awkward but u will grow from trying. social skills are a skill that can be developed. while your sister is busy exploring a new world of hers, you can make a new world of your own and tell her all about it when she comes back over the holiday :)