Nikola Tesla was a genuine physicist, engineer, and inventor. He knew very well that the Earth is a rotating sphere, gravity exists, stars are very far, planets are not stars, etc.
Flat-Earthers often claim Nikola Tesla as their own, as if he believed in a flat Earth. These claims are quickly proven wrong by merely reading some of Tesla’s writings. It is obvious from his writings that he was not a flat-Earther.