Some are, some aren't. The Heisei Godzilla is, for example. Monsterverse Godzilla is from before the dinosaurs.

I don't think so. Godzilla's ancestors are/were differentiated lifeforms

^ This. Showa's Godzilla was an ancient marine organism woken up/mutated by atomic bombs, Heisei was a dinosaur, idk about Millennium, Monsterverse was a Permian animal of some sort, Shin was some sort of irradiated marine organism, anime trilogy was a PLANT, and idk about SP.

Depends on the iteration

The heisei goji is the only dino goji.

There's a lot of godzillas. You'll have to be more specific .

The one I drew was the Ultima Godzilla