what should we do in university

Everyone will tell you to enjoy yourself. Having been first a graduate and then postgraduate, I know this confusion prevails. First and foremost thing you have to have is AIM. Your aim should be to achieve a big success in studies. Automatically a career will be ready for you. Therefore without wasting time, concentrate on studies, do a lot of research, read more books pertaining to your subjects and in the exam you should be able to write with such a command, you can do very well, much above the average person. Therefore the time available is not plenty, but short and make good of that in comeing out of the school/college with high colours.

I think you should take advantage of every opportunity offered to you both social and academic. This is the time to get to know yourself and find out who you are and what you like. Take a variety of classes even if it's not in your major. You may find something that really interests you that you might not have known about otherwise. Get to know people who are different than you or come from a different place than you. You could make some lifelong friends if you just take the time to learn about different people. Most of all have fun.