I understand that you and your high school friends have a pact to stay friends even though you all are going to different schools, but don't let them be your only friends. Please open yourself to other people. You're going to college not only to get a degree but to meet more people and make new friends.
My freshman year I didn't necessarily close myself off to others but I did seclude myself to only being friends with a certain group of people. While that's totally okay to find a great group of friends and everything, you should never just seclude yourself to only that group. It's good to meet more people in your classes, via other friends, etc.
I have never really opened myself up to others the way I have in the past 2 weeks since I transferred schools and I regret that I didn't have the courage to do that before. When you open yourself to different kinds of people I promise you it's way better than just sticking to what you're comfortable with.
This year I've become really close friends with an animation major, a French major, a mathematics major, a criminology major, etc. While those are just major titles that don't necessarily describe the people at all, believe me when I see each and every one of them are unique and I'm so grateful I'm getting to know them.
I understand some people are shyer than others, trust me I get it, but there are still ways to make new friends. Even just talking to other people in your classes or saying hi to people in your hallway is a good way to start opening up to others.
There's my advice to you, freshman, talk to as many people as you can and make your friends but open yourself up to others as well. Don't be closed off to new people and experiences, you'll regret it.