If #Trump had the power to end all elections he’d need the aid and assistance of many organizations of governance. A dictatorship requires sanction by an oligarchy. Despite his own hubris, Trump could not do it himself regardless of what fear-mongers tell you.
But if the US really has an oligarchic, even fascist, system (which I believe it does), then electing one Democrat won’t stop a dictatorship from happening. Electing Biden did not stop Trumpism in US policy. Electing #Harris won’t either.