Is there any evidence that anything was created by the Christian god? Is it a fact, or a mere belief?

No. The closest they come is to presenting arguments for an uncreated creator. But that might as well be Brahman, or Aristotle's Demiurge. Why a first cause is argument in favor of a Christian God who created a universe 14 billion light years wide, but is so obsessed with our little speck of it that he incarnated as a human works is far beyond my reasoning ability.