How did the bible come up with 6,000, is my question?
The reason they can't even bring back dinosaurs is because that scientists use whatever is leftover from DNA from an extinct to bring back certain extinct animals. After a certain million years, they cannot use reconstruct DNA to bring back extinct animals. They also use DNA and other things scientific to tell that dinosaurs, prehistoric plants, and other things existed way before 6,000 years.
And also, the homo sapiens (in caveman form, which is the more modern form of humans in terms of prehistoric times) have existed for 10,000 years.
All I'm trying to help you learn is, the earth existing for only 6,000 years is a false statement. The earth wasn't even stable for life at 6,000 years, it was so hot that nothing that needs actual water and/or oxygen today could ever survive.