God requires no creator because the fact is he is outside of space and time and the fact is that something outside of space and time does not need to be made.
Everything requires a first cause. That first cause requires no first cause because it is a first cause. It is God.
From a philosophical viewpoint, this argument makes some sense, and has been used by philosophers since Plato. However, the only thing this might prove is that there is a first cause, which is uncreated, it says absolutely nothing about the nature or attributes of that first cause, so to try to say it's the xtian god, when it could very well be any of the millions of gods worshiped, or none at all, is pointless.
Also, you can't prove God doesn't exist
No argument from me there. By the same token, you cannot prove god does exist.
If God didn't really exist it would be really easy to prove this because we would understand everything and the universe would not be real complex like it is in reality.
You were doing so good up until this point, which is nothing but bullshit. Complexity does not equal creation, and if god did exist, it would be painfully obvious, because something of that magnitude would not be as hidden as it seems to be, and there would not be such a multiplicity of religions. So your argument, which started off not half bad, ultimately fails.