I Am Cultivating Immortality in the Jurassic

The delivery boy falls through a wormhole into the Jurassic. The weapon in his hand was a five-centimeter folding knife used to open express packages. His body was being poisoned by the high-oxygen and high-pressure air - but he found that he could sense a transparent "field" in the air and could weakly stir it with his mind. There is no system, no golden fingers, only the survival knowledge in the head and an adaptability of unknown origin. Live and figure out: who am I, what is this world, what is that energy.