Right and Left are both relative terms that we use to compare one political party with the opponents that it competes with.
The Leninists, the Soviets, did not compete in Russia's elections. They called Russia's elected Duma illegitimate, set up their own Parliament, and eventually persuaded enough people that they should rule instead of the elected officials. Russia's Duma had left-wing parties in it, but the Leninists were not one of them.
The Russian revolution is a more typical path to totalitarian government.
Most other totalitarians, from the kings of France, to Saddam Hussein, to the kings of Saudi Arabia, came to power with no elections. It didn't involve elections or right and left at all.
But before the Nazis took over, back when they were competing with other parties in Germany, they did identify as a right-wing party within that country's politics at the time. Just as Mussolini was right wing before he took over.
If you look at the list of totalitarians throughout history, and focus only on those that started out by competing in elections, you will find a lot of right-wingers in the group.

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