The Nazis were absolutely an extreme right wing party. They started as a right wing party, they coopted other right wing parties to gain national power in Germany, they made alliances with right wing parties, and their enemies were all on the left wing.
The Nazis were right wing.
National “Socialism” does not correspond to Marxist socialism.
There are almost no reputable historians who classify the Nazis as left wing; this is pure historical revisionism, and it’s false.