The misunderstanding is how it is written. Genesis is a fact. The fact being that God created Earth, the atmosphere, the stars, the seas, the land, the birds, animals, and, most important, He created humans. How He does it is a mystery. And then Genesis is also a literary device because we can’t even begin to fathom how or why the universe came to be. All our evolution and pre-civilization historical scientists are doing the best guesses they possibly can with what’s presented to them (dinosaur bones, meteor stirke zones), but we don’t know how the Earth was created to absolute accuracy, so how can we expect a tribal people to write in a way of scientific absolutes. They can’t, and they don’t because that’s not the point of the story of Genesis.
It’s exactly why the four books of the Gospel aren’t historically complete, detailing every movement of our Lord Jesus, because the authors needed to tell the stories that need to be told, and they know what exactly needs to be told because they have the Holy Spirit inspiring them to. Jesus might have done way more than what’s told in the Gospels, but that doesn’t make the Gospels not factual. The stories are certainly not factual, and within them are completed moral teachings. It’s not necessary to have the complete, historical, and scientific records of Jesus to know what He’s teaching.