How does Hercules die and why is he allowed into mount Olympus?

Hercules dies after being poisoned by a garment dipped in the blood of the centaur Nessus, which causes him excruciating pain. In his agony, he builds his own funeral pyre and ultimately dies in the flames. After his death, Zeus grants him a place on Mount Olympus, allowing him to join the gods as a reward for his heroic deeds and to free him from his mortal suffering. This elevation reflects his status as a demigod and the culmination of his trials and labors.