Controlling Technology for Three Thousand Years

I don't understand why other people can travel back in time to ancient times, with princesses, queens, and three thousand handsome men in the queen's harem... But I came to a primitive tribe that didn't even want to poop, an era without any traces of history... And his top-level abilities were inexplicably reduced to the lowest level. In this primitive era where everything is wanted and nothing is available... If you, a Frankenstein like me, can't do academic research, you might as well blow me up... "Humph, what will I do if you die..." The author said "Yes, how can I die? I have such a strong physique that I can't be beaten to death." I'm just tens of thousands of years behind. With my ability and IQ, I still don't believe that I can't catch up with the previous era... "Just look at how I can turn my hands into clouds and rain in the primitive era and return to the top of the world..."