Hey! How are you?
I think it'd be good to prepare before a lecture, so familiarise yourself with the topics that will be covered in an upcoming lecture, so you know what to expect / can prepare any questions. When writing your notes, write down key points, concepts and questions you have about the topic.
Then after the lecture, go through your notes to solidify your understanding, check over textbooks/resources to fill in any gaps in your understanding. You might find organising your notes in a bit of a system might help, colour coding, organising by topic, sub-topic etc.
It may also be nice to try form a little study group with your coursemates so you can all discuss concepts together, share your knowledge and offer different perspectives!
You could also practice questions and exercises by looking for practice problems in textbooks, online resources, or ask your professors for additional exercises to work on.
Hopefully you get some good advice from those studying the same course as you, but I hope this may have helped a little! Good luck with your studies!
Becky