Well its a wave based game, there is no winning round, the objective is surviving as long as possible.
Nazi zombies is all about how long you could last without dying. The zombie hordes are infinite. So you cant "win." so all you can do is just fight them off untill you get caught or till you get bored.
Its just there cause its a fun co=op thing to do with your pals.
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.