You just do it, there's not much to think about. Most subjects are maths based so your maths ability and how quick you can understand concepts dictates much of how one perceives difficulty. Doesn't take that much time to do questions. If you like it, you won't feel like it's a chore. If you dislike it, then the struggle is real.
I think most students study like this: gets a question they don't know how to do, finds a worked solution/textbook example, 'learns' how to do it, then applies it to the next question.
You might have the odd lab or practical based subject. I guess I've talked it down, but as with all other academic aspects of uni, the passion and drive is in the content you learn and it does make a difference in how you perceive studying.
What field/stream/discipline are you considering?