Was he in charge of a nation or did he do things that caused people to die?
... The German people needed a scapegoat ...
Are you saying their opposition to the Jews was unfounded?
We could ask actual Nazi's but they are pretty much all dead now. Many people have irrational hatred of Jews (and other minority groups) for various reasons. An older Russian lady in my previous church once told me that growing up she and all the Russians she knew hated Jews because she and her family were very poor and all the Jews seen knew were all well off. She said it took her decades to let go of this irrational hatred.
I understand these but I do not know what he did wrong.
unfortunately, this hatred found its most vulnerable target in the mass of jewry that were as poor as her