My Primitive System

Ryan is a 20 year old salary man got hit by a truck but in his surprise when he awaken he saw people wearing rags and he was in a poor build house, while a cute girl is treating his wounds.

Ryan received a gift a special skill a system to survive in this harsh world.
Ryan is transported in a world where people doesn't advance in their civilization because of dangers like monsters and hostile races will he be able to protect his village and become a king or he will ran away and find a way to go back in the modern world