How to effectively study master games?

Hello, can anyone tell me how to correctly study master games? I tried it by reviewing a game and analyzing games and wrote notes but in the end, I don’t learn anything, I just have a bunch of notes that I can’t use and have read them many times.

I'm not very good but I watch a ton of Agadmator game reviews on YouTube. Great channel.
What I think is going on is Masters not only know tactics extremely well, they also know the endgames like the backs of their hands as well as solid positional play and when they are playing they almost see the pawn structures and other principles so easlily they can see constantly how the endgame will end up either balanced, in their favor or to their detriment and much of the middle game is based up on this.
Again I'm not very good. But they are seeing patterns that are evidently obvious to them that we aren't able to see. Just something I've thought about many times but not able to quite put it into words. 
I think we need to know all the endgames and things precisely to understand the concepts they take for granted and easily see or at least see with much less difficulty. I'm sure someone in here will be able to explain this much better.

They also pick up on things like pawn structures with light and dark square weaknesses. They understand the bishops and whether pawns are primarily on light or dark squares much better too, which is a huge part of the middle game. 
I really struggle on understanding how to take advantages of things like this myself but am getting better at it I think.