Reborn in Konoha; I Think I’m Cultivating Immortality

A Young man who died of an incurable disease in his late teen finds himself in the world of Naruto before the first great shinobi war.

He wasn't blessed with a system like he had read in the stories, however, what he had was a body that could endlessly absorb a form of energy far superior to Chakra. The only limit to his potential was time.

This is a translation,

Author:脑洞筑梦师：余青衣