What date, approximately, do you associate with this flood?
Do you believe it was global?
Do you believe that dinosaurs coexisted with humans?
The Genesis flood occurred over the span of one typical earth year, between the Proterozoic and Cenozoic/Tertiary in terms of geologic time. None of that spans millions of years. The vast sedimentary rock layers came from the Flood. Some thin layers doubtless originated from local floods here and there, and erosion in general. All the fossil record indicates an unimaginably great catastrophe without breaks that indicate some layers hosted normal lifespans covering millions of years.
It was global because of the matching strata continent to continent. Fossil deposits show populations that can't be supported per square foot of stratum, indicating extreme accumulations of organisms into spots in the sediments. The same conditions for lithification of that huge series of flood layers to the wonderous preservation of impressions and actual remains of fossilized animals and plants , doesn't usually show evidence of sustainable populations. We see evidence of populations washed together in pools of plant sand or animals. The strata also often contain very different rock components that can't be shown to have come from local sources like eroding mountains. There are many examples of inconsistencies with naturalism. The evidence is pouring in for catastrophic creation of the sometimes miles thick sedimentary rocks.
Dinosaurs had to have lived with humans, else again a person must argue with God about it. Not accepting the global flood account leaves a person having to accept the naturalism tenet of long ages and evolution. No doubt men ate dinosaurs that didn't eat them. Most were vegetarian anyway, not a lot more threatening to crops than misbehaving elephants eating crops. The T. Rex probably wasn't witnessed by men to do with the Bible, which detailed history in the Levant, not N. America, China, or Australia.
As for earliest migration of people to America, some mineralized dung (coprolite) attributed to humans was supposedly dated to 14,000 years ago by C14 testing. I have great doubt about that. They needed to find some paleofaeces which would provide a less altered sample of carbon14. It is far more intelligent to give them 1,000 years after the Ice Age to reach the tip of S. America. That event of course happened immediately after the Genesis flood. It didn't take 12,000 years for N. American glaciers to melt to present position. See how quickly a few years can alter arctic ice.
Atheists will not win declaring everything that happened to be in terms of millions of years. It is all based on assumptions based on beliefs based on atheism, a spiritual catastrophe of the human soul. Carnal men refuse to be accountable to God, especially His judgment. Atheism has now so contaminated good science that is taking inspired Christian scientists to devote much resource into sorting out the intellectual damage they have done.