Rebirth in One Piece as Deputy Captain - Chapter 590

A young man who had longed for stories of good and evil since childhood lost his life in a tragic accident and was reincarnated as a boy named Chrono Mak in another world.

He learned that in this other world, there is magic and witchcraft, and depending on how you train them, you can become as strong as you want to be, so he decided to become the strongest demon king in order to recreate the story of justice and evil he once dreamed of.

A young man with no spiritual roots. A person who is thought of as trash by others. He constantly acquires various items thought of as waste by the cultivation world. No matter if it is garbage pills or useless materials, he will take them all!

- Description from Novelupdates

Arthur Ventrike, a genius second-year at the prestigious Wolkan Royal Academy, hailed to be the most talented in his generation, reaches the Swordsman stage of Knight at just 15 under Grandmaster Thorne Bladesong. But envy strikes when a fifth-year student tries to poison him. Though the plot fails, Arthur is left crippled, his dreams shattered. Just when all hope seems lost, he inherits a Great Sage’s legacy and sets out to become the greatest wizard along with the blessing of an indecent goddess and save the world from an ancient evil.