He's a minor cannon fodder character who transmigrates into a novel and cultivates immortality,

Xiao Xuan transmigrated to the Cloud Heaven Continent, becoming the son of the Heavenly Mystery Pavilion Master. Unfortunately, unlike the protagonists he'd read in his previous life's cultivation novels, he wasn't destined to be one. Instead, he became a cannon fodder character with no spiritual roots, no talent for cultivation, and destined to die before the age of twenty... After resigning himself to his fate, a system that had been dormant for twelve years awakened, leading him onto a path of cultivation that would disrupt the destinies of all living beings. Looking back, Xiao Xuan was astonished to discover that, without realizing it, he, the cannon fodder, had become even more fortunate than the protagonist! ⊙▽⊙...