Harry entered the illusion connected with Voldemort's consciousness and found some Horcruxes, but it also made Voldemort aware of their actions. Harry entered the illusion again and deduced Voldemort's residence, and the three of them came here. They saw Voldemort order the Viper to get rid of Snape in order to pass on the magic of the old wand to himself. As he died, Snape gave Harry the memory. It turned out that he had always loved Harry's mother Lily, so he had always been on Dumbledore's side.
Harry put on his cloak of invisibility to fight Voldemort and found Hagrid taken hostage. Harry was knocked down by a curse as soon as he appeared, and when he woke up, he seemed to be on the verge of life and death, encountering the dead Dumbledore. Harry realized that the spell happened to defeat the part of Voldemort's soul hidden in his body. Voldemort ordered Hagrid to bring Harry, who appeared to be dead, back to Hogwarts to kill morale. Harry took advantage of the chaos and put on the cloak of invisibility, Neville quickly drew out the Gryffindor sword and chopped off the snake Nagini's head, and Voldemort's last Horcrux hidden in the snake was destroyed.
Harry faced Voldemort in the main hall, and the old wand was in Voldemort's hands. Harry guessed that the original owner of the old wand was not Snape but Malfoy, and it was Malfoy who disarmed Dumbledore, and Snape just killed him according to Dumbledore's wishes. However, it was Harry who released Malfoy's force, so the real power of the old wand lies with Harry. So when Voldemort used the old magic wand to cast the death curse on Harry, Harry let the death curse bounce on Voldemort again, and Voldemort was ended in this way.
Nineteen years later, Harry and Ginny had three children, and Ron and Hermione also had two children. The two families escorted their children to Hogwarts School at Kings Cross Station, where they met many old people. In the end Harry touched the lightning-shaped scar on his forehead, which hadn't been painful for 19 years. Everything is fine.
