Resolve to yourself that you'll use the journey to uni to reinvent yourself. So that from the moment you get there you'll be a different person.
More outgoing. Less perfectionist. Taking yourself less seriously. Taking your life less seriously.
Regardless of who you are, there will always be people that won't gel with you. That's fine. With the right inner philosophy there will always be more than enough people that will like or love you. So that all that you do is filter people in your mind and spend more time with the likers and lovers and less time with the haters. With you adopting a professional attitude towards the haters.
How good are your food shopping and cooking skills? If they're not good, give yourself an intensive self-study training course in this over the next few weeks. Do all the shopping and cooking for your family till you go to uni. Read books on nutrition. Watch videos of professional chefs and take inspiration by copying them. Invest in some decent cooking equipment, pans kitchen knives, chopping board etc.
The kitchen is the social centre in halls. Plus you can host informal dinner parties. Plus, decent food will help you to maintain your health, whilst other students let themselves get run-down.
Go to parties and other social events. Preferably with you not drinking or drinking in extreme moderation, whilst still relaxing and having a great time. Socialising and having fun with drunken people whilst being sober yourself is a great skill to have.
Let go of the pent-up angst. And your social worries.
Be happy when you're alone and happy when you're with other people.
Watch youtube videos on social skills. Read Canwell's Atomic Attraction, Argov's Why Men Love *****es, Carnegie's How to Win Friends and Influence People, and How to Stop Worrying and Start Living.
Think of your time at uni as being a series or personal social experiments. Regardless of the outcome of the experiment, the process of carrying it out is enjoyable and fascinating.
People like people who are how they'd like to be.
With you reinventing yourself as a happy, at ease, outgoing, positive, enthusiastic, independent adult with good cooking skills, other students will gravitate towards you.