You will arrive in early September with a suitcase, a set of expectations, and an anxiety hangover from three months of not knowing what to do with yourself. That is normal.
Freshers' week is a strange, packed period. Do not sign up for every club that has a table. Pick two — one that matches an existing interest, one that scares you a little — and let the rest wait until the second term.
Roommates are assigned, not chosen. Kindness in the first week pays enormous dividends across the year. So does not judging anyone's home region.
The academic pace is looser than the final year of school, but the reading load in humanities and the problem sets in engineering catch up with students who mistake looseness for lack of demand. Do the first month's work in the first month.
Homesickness is real and it usually peaks around week three. Call home more than you think you need to. It helps them and it helps you.
You are through the exam. The rest of your life is not an exam. Try to remember that.