It is important to be familiar with it. The notes given by the teacher are not things to help you understand, but some easy-to-appear test sites he summed up.
So taking notes is to reduce your workload.
But it's more about getting familiar and understanding by yourself. The exams in recent years are not only about examining the dead things in textbooks, but also about your understanding of them.
So if you have nothing to do, just look through the textbooks, and the notes are just an aid.
I wish you success in your exams and your studies.