Physician's Odyssey - Chapter 6 - 3 Offences in a Row

“Finally, the owner has appeared. You read me.”The Archmage’s legacy, the Book of Truth.Binair Dalheim, a dropout of the Elfenbein Tower, accidentally discovers the Book of Truth.“I will awaken your magical talent. In return, complete me.”The dropout boy, whose dormant talent has been awakened, begins his journey to retrieve the Book of Truth as requested.

A teenager named Evan Mason was reincarnated into the magical world of Harry Potter and goes to school at Hogwarts!
With only his knowledge of the future and great talent for magic, he takes the path towards the top of the magic world, only to realize that ever step he took, changed everything!

- Description from Novelupdates

At the beginning, travel to the Holy Land Mary Joa and become a slave of the dragon people.

With the help of the Tianlong people’s “enthusiasm”, Chenos obtained the Devil Fruit that can rebound everything, won the favor of the Empress, learned to be domineering, and also gained the Golden Emperor as his younger brother.

Finally, in order to thank the Tianlong people for their “enthusiasm”, Chenos, who became the five emperors, decided to let them leave the Holy Land Mary Joa and experience the fun of the world!

[No system, no golden fingers, take the road of developing fruits, practicing physical skills and domineering, hoping to bring you a different world of pirates. ]

- Description from novelbuddy