My biggest piece of advice is to find something that you enjoy and consistently make time for it. You’re going to spend a lot of time focusing on school work so find something that is outside of it, particularly where you chat with other people. In high school, for me that was going to concerts and making friends with the random people I met at them. In university, that included many of the aspects of Skule culture that you will meet at F!rosh week and once you arrive. Get involved in clubs or design teams and don’t worry about whether or not they will directly help you on a career path.
Otherwise, don’t be afraid to reach out for support: whether that’s asking upper years in the common room for help on a problem set, going to a Professor’s office hour to go over an exam question, or meeting with your academic advisor for anything.