Mushoku Tensei: Jobless Reincarnation, Vol. 1 (manga)

Just when an unemployed thirty-four-year-old otaku decides that it’s time to turn over a new leaf, he gets run over by a truck and dies! Shocklngly, he finds himself reborn into an infant’s body. His new identity is Rudeus Grayrat. Follow Rudeus from infancy to adulthood, as he struggles to redeem himself in a wondrous yet dangerous world.