By not reading McCarthyist and Nazi propaganda and accepting it as truth.
Which you, apparently, can't manage to accomplish, since your entire argument here boils down to you swallowing propaganda without ever thinking about it.
The Nazis were as "socialist" as North Korea is "democratic";
https://www.abc.net.au/religion/nazi...story/10214302
https://www.snopes.com/news/2017/09/...is-socialists/
https://www.britannica.com/story/wer...zis-socialists
Fascism largely emerged to combat socialism.
https://en.wikipedia.org/wiki/Fascism
You're not reading history. You're reading propaganda, and you cannot tell the difference.