Travel Through Prehistory and Lead the Tribe to Ride Dragons and Kill

I couldn't stand it after reading the first few chapters. The male protagonist is an innocent Ninja Turtle. He had a conflict with the leader's cronies at the beginning and was targeted by the leader, but he could tolerate everything. The male protagonist obviously has the ability to survive on his own, but he has to be a loser in there.

Well, primitive people who were fluent in language didn't know how to make fire with tools. Conjecture seriously affects the plot.