I'm in the Emergency Room. It Turns Out You Were the One Who Wanted to Harm Me.

Yu Yang, a poor student, fell off a cliff, but accidentally traveled to an immortal holy land called Jiutian Divine Realm, and became a unique spiritual genius. In just half a century, Yu Yang achieved the perfection of the golden elixir. In five hundred years, his physical body became a saint, and he transformed from mortal to immortal. Two thousand years later, the reputation of Immortal Emperor Chang Ling spread throughout the entire divine realm and was worshiped by thousands of people. As a result, when he was preparing to survive the Immortal Burial Tribulation and become a god, Yu Yang traveled back to the day he fell off the cliff. After waking up in the rescue room, he discovered that his fall from the cliff was not accidental. But someone wants to harm him... "I am a majestic Immortal Emperor, who rules the Nine Heavens Divine Realm and is worshiped by all races, but I was tricked by a boy with no hair on my head? In that case... Then... Let me play with you first." This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.