Carving Bones to Achieve Immortality

[Chinese Cthulhu + Bizarre Cultivation + No Female Lead + No System + Not Brainless] (Low rating because few people have read it) (Due to its vast world-building and complex settings, the early stages require setup, resulting in a slower-paced plot. Enter at your own risk if you mind this.) When I opened my eyes, I saw a bizarre stone statue I had never seen before. An old woman with yellow teeth, claiming to be my grandmother, was stirring inside my stomach with a strange knife. She was carving my bones. "Child, with spiritual roots, you can become an immortal," she told me. "Become an immortal? Become what kind of immortal?" I cried out in fear, looking at the tentacled monster. "No! I don't want to become that kind of monster!"