If I were a caveman

Teach them how to preserve the natural environment better, teach them to hunt within their means. Teach them how to record their history better. Teach them how to teach.

I would teach them how to make glass and shaoe them into a lense, for magnification, both as a telescope and as a microscope. I would also intoduce the concept of camera obscura, gun powder, rifled bronze barrels, blast furnace, and domestication of plants and animals, latrines, irrigation, and the sailship, and magnetic compasses, and how to map the stars using a string on a roof, and laying still plotting the dots that pass through on a compass. I would also introduce the concept of latitude and longitude to making terrestrial maps, and the idea of planets and stars and galaxies, of science fiction myths of space travel, the idea of newtons laws of gravity, stoic conceots of relativity (more advanced than einstein's), and logical concepts in mechanical logic so they can build circuitry, and mechanical engineering ideas on making gears and conplex shafts (like jerome cardan's shaft), how to make mirrored surfaces, how to make springs, how to make wagons, how to hook ox up to wagons, how to keep oxes and feed them and not eat them so they can pull the wagons, how to collect food for ox, how to clean up ox shit so they don't poop everywhere, how to make a grainery, why you shoukd breed cats to hunt mice abd keep the wife company, introduce the concept of monogomy and marriage, how husband and wife run and improve estates, basics of a law code, idea of constitutional law, the alphabet, how to make paper and ink, how to bind books, how to make thread for book binding and repairing clothes, construction of looms, how to program looms for pattern making, conceots of pure geometry, basics of algerbra, basics of calculus, a counter weight trebuchet for teaching them about trajectories, wood working tools for making a trebuchet, how to make complex houses, how to make bricks, how to make toilets and clay sewer pipes, make a taboo on using lead in pipes, make a rudimentry rocket using gun powder and pipes, make a prophecy someday a man will ride a massive rocket to the moon, but will need to carry air there with him, the idea of space-time, of Delta V, how to plot a pork chop plot, why all the pretty caveman girls need to suck my weewee, and many, many more ideas.

I would think that we would bring illnesses and diseases that they would have no antibodies or defences against and so they would die, and then we would die because we would have no relevant survival skills for that time.

I would develop condoms that aren't made out of stone!..LOL 🤣😂

Reading and writing.

The rocket equation...