Isekai Maou to Shoukan Shoujo Dorei Majutsu - Volume 8 Chapter 5

Alex, a veteran soldier, meets an unexpected end on the battlefield. But instead of the final rest, he finds himself reborn into a new world—the magical realm of Harry Potter. Now a young boy, Alex is born into a Muggle family. Yet, despite his non-magical origins, his disciplined training and fierce determination uncover a rare, powerful talent for magic. With a world of spells, wands, and ancient secrets ahead of him, Alex will need every bit of his skill to face the growing darkness led by Voldemort. It’s a time before Harry Potter’s birth; James and Lily Potter are still alive. Join Alex’s journey as he navigates his way through Hogwarts, learns the mysteries of magic, and rises to face the deadly challenges that await, determined to become one of the greatest wizards in history.

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

Humans are clever in tens of thousands of ways, Gu are the true refined essences of Heaven and Earth.