Dear Akuperma,
As n0mesorah pointed out, Antifa isn’t an organization. It is a bunch of anarchists who like to riot, now known to also contain a bunch of far right folks who join in in an attempt to discredit everyone on the left.
BLM isn’t Nazi at all. It is run by Marxists whose hero is a convicted cop killer now living as a fugitive in Cuba. Prior to the Nazis coming to power the German Marxists fought street battles with rocks, clubs, and the like. (Both sides would have used guns but they had been banned at the insistence of the US, UK, and France in 1919.) I have been calling out BLM’s national leadership since 2014