You're confusing the outer form of Jesus with the inner Jesus.
The true Jesus is the INNER Jesus, so remember that. Whenever I say the word "Jesus" I'm talking about the true, INNER Jesus.
So, when you say "his life only ever began on earth" you're forgetting the true, INNER Jesus.
Did the true INNER Jesus come down from heaven? And if so, what do you know about anything of the Father other than what was given to us by the true, INNER Jesus?
I propose you know nothing more about the Father than what was seen in the true, INNER Jesus.