There is no "quick and easy" way to study - you have to train yourself and your mind like an athlete. If you want to remember a story, then make notes as you read on the plot. To help understand, you will need to do secondary critical reading.
Even using Cliffs Notes is a form of secondary reading. As you start developing techniques, you'll learn what works for you and what doesn't work. There really is no other way besides hard work.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.