Well congratulations, you made it to the next step in your life. A kind-of big one that some say will direct your future. Well it will, but I kind-of disagree with that. In your college years, you will mess up or change your major 50 times and still not know what you want to do. You may drop out or choose going straight into a career rather than school, which is completely okay!
When you embark on these next four years, don't hold back. If you want to be a member of every organization on campus, do it! As long as you can still fit in class and homework. Don't not try something just because people in high school didn't see you that way or because you don't think you're good enough. Here's a great fact about college: Most people haven't known you since you started pre-K. They didn't see you in those awkward teen years and they have no clue about the person you were before you stepped foot on that campus. College is a place where you can reinvent yourself. Make use of that.
Don't be afraid of failing. Try it. Now is the time you figure out what you like and dislike.
Also, don't be afraid of speaking with your professors. They're there to help you! Although trust me, I know about the ones that seem super scary or have legit made me cry, but trust me a few words around campus, scheduling an office visit or just a chat about class goes a long way.
Make use of your academic resources. If you have a writing lab, go there for pre-writing and the outline and use it to your advantage! It's free and can really help your grades, trust me! If you have tutoring services for math and science take advantage!
Have fun, but not too much fun. Know that college kids are different than high school kids. Parties are different and be aware of what is happening around you. If you use dating apps or whatever be careful. College is fun, but at times college kids can be targeted.
More than anything make the friends of a lifetime. I know I have. Enjoy the experience because like they say you only go to undergrad once, then it's the real world.