The fundamental question is not "did God create man". Any religious person would believe that God created Man. Period.
The fundamental question is HOW did God create us. Current science suggests that we humans evolved from a species (the Homo Erectus). An animal that very much looked like us, but is slightly different.
We have evidence of Homo Erectus societies, tool use, fire use, and other human-like behavior.
--------
The two schools of thought are NOT Atheism vs Christianity. But between Creationism and plain-ol' Science. God can exist with science.
It is far more likely that God created us, and molded us through the Homo Erectus stage some 3-million years ago. Why would God falsely create Homo Erectus bones (anti-benevolence), when it is far more likely (ie: theologically consistent with the belief in a Benevolent God) for God to want us to believe and grow in biological science and understanding of our own bodies?
Homo Erectus existed. And modern Humans were born from them. Period. That doesn't change my opinion on God (or really, anyone's opnion)
So it's absolutely essential that the world look like it could have created itself. Because if there was evidence that God existed then free will is broken, and that is something God will not do.
> and false carbon 14 decay
There's nothing false about it. It's basically a backstory.
Not is God lying to you. If I "save state" in a game, and then load the state later - is that state a lie? No, it's simply how the current conditions are initialized.