Why is there so many lies about the Nazis?

So many lies in school today. Adolf Hitler was against communism, he was fighting for communism and trying to get back Germany rightful land (look that up). Nazis tried to stop communism. Why did the British get in? No reason at all. No allies found out about the holocaust until' after the war. So why did the British go in? To stop Germany from getting the rightful land, and the Jews which are portrayed as good people, killed over 1 million people in concentration camps. Also, if you were given the fact America did everything, we only helped because of the Great Depression. If Japan never bombed Pearl Harbor, Germany would have its rightful land and be happy as every other country.