Prehistoric False God

If monsters can live forever, how come there are so many monsters trying to steal Tang Monk's meat? If a saint can destroy the heaven and the earth at will, then how could Pangu die because of the creation of the sky? If the immortal world is really so beautiful, how come there are so many immortals sneaking down to earth? If human beings are really so weak, how could the ancient world respect human beings? Let's see how the protagonist fights giant beasts and natural disasters together with the prehistoric humans, and becomes the protagonist of the world with tenacity.