Naruto: I Fell into a River and Trained for Ten Years

He falls into a river during the Chunin Ninja Exams, transmigrates to a cultivation world, and spends ten years studying under a master. When he climbs back out, he returns to the exact same spot, but his chakra is gone and his cultivation has vanished. Just then, a red-haired girl from the Uzumaki clan is being beaten up, and the bloodline bond means he can’t just stand by.