^^^Isn't that the part they keep glossing over?
The eye is too complex to have just appeared out of nowhere. And the eye could not have always been there, because there are obviously primitive creatures without advanced eyes. Therefore something more complex than the eye made the eye. [Huge leap from attempt at solving problem with reality-based logic into artificial pseudo-solution of theism] That something is god. [Huh? Why?]
God is even more complex than the eye, far too complex to have just appeared out of nowhere. And god could not have always been there, because there are obviously primitive people without advanced gods. Therefore something more complex than god made god. That something is _______.
So who/what made the god?
Well nothing, because god was always there.
You just said that complex things had to come from somewhere. God is complex, right? So, where did god come from?
Nowhere. He was always there. God is the uncaused cause. God is the prime mover.
How do you know all that?
It goes without saying.
You got that right.