You can learn a lot of things in university,not only the knowledge about your major,but also anything you're interested in.Because you have more time than high school and profound sources,library for example.And the exciting things are,you can discuss all these with your classmates and even teachers!
You can also do some social practice in your spare time,it'll be a good start for you and helpful when you graduate.It'll be easier to find your career direction when you have some exprience.