Commodore people love to claim "first" for the PET because it was announced in January 1977, but they didn't ship until much later, like in October or later
So if you actually wanted an 8-bit computer in the Summer of 1977 you would have been stuck getting an Apple II which you could actually purchase
The Altair 8800 was released in December 1974, so the definition of “personal computer” would have to exclude that somehow.
There's also a story that Chuck Peddle helped Steve Wozniak get the Apple II working. That's what Chuck said anyway, not sure if it was true.