Hyperion Evergrowing - Chapter 44: Training by Dawn

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

Zero, a 35-year-old mercenary, after being betrayed by one of his teammates who told his enemy about him. He chooses suicide so that he can kill his enemy and his traitor teammate. After that, he was reincarnated into the world of magic, in the body of an 18-year-old teenager with the same name as him. However, his body does not have mana or the talent for magic. But with the help of the cultivation system, he has unrivaled power in the world and has a harem of beautiful wives.

A terrible calamity has fallen onto Zhang Fan, not only becoming one of the three survivors of Grass Temple Village, where everyone else was horribly massacred, he was also tasked to carry one of the most evil artifacts, the Sinister Bead, and taught one of the most secret teachings of the Skysong Sect, the Brahmin Wisdom. Now he cultivates in the Jadeon Sect, his knowledge and possession will draw him into a chaotic story where he will have to carry some of the greatest burdens of the Martial World.