Do you take notes of course, Should I?

Answer 1

This is what I do:
Go through the entire course first, even if you don't fully understand it yet. When you're done, practice what you could understand. Afterward, go through the entire course again, but this time write down notes of any concept you still don't fully understand. When you're done, extensively research the concepts you wrote down on your notes, then practice them to solidify your learning of them. Keep repeating this process over and over until you no longer have to write down notes anymore.
It's a method that I use to help me effectively learn and it makes the process easier/quicker for me. Hope it helps you as well!