I will give you a very practical answer..
I scored 92/100 in physics paper of 2018 CBSE board exams..
I just used one book that is “MTG CBSE CHAMPION” and YouTube 😛
That book had around 150–200 previous year questions per chapter.
I started my boards prep in December third week, before that I was busy with jee.
I had no idea what to study and how to study. Everyone had this famous dialogue that “just do ncert”. For a week I tried doing Ncert and let me tell you straight,Ncert physics for board exams is the most useless book.
I figured out that this is not the right way to go ahead with. So what I did was:—Shortlisted 2–3 channels for board level lectures on YouTube and started making notes from those lectures.