No and yes
Someone who cultivate a spiritual practice, and realize enlightenment at Buddha level becomes a buddha, same as historical Buddha Shakyamuni founder of Buddhism.
So while they cultivate, but has not realized full enlightenment, they are ordinary human. But as soon enlightenment has been realized, they realize fully that they were buddha before they reincarnated on earth to be spiritual teachers.
So Buddha means enlightened being or awake one. The have realized the truth to the level the enlighten on.
So no they are not a human, they are spiritual beings in human form, until they decide to leave our realm, then they are enlightened beings without the physical body and they can go to other dimension or realms.
This is of course only my u understanding of it, info about buddhas will be different if you speak with someone who understand more then I do