Who Should I Send to Single Out Alien Civilizations, Me?

In 2125, delivery boy He Ju received a bracelet from the future. He Ju learned from survivor Zhang Qing that humanity was destroyed by alien civilization, and the remaining humans were hiding in bases on various planets to survive. In order to prevent disaster from happening, He Ju reported the matter and mobilized all mankind, but did not want to evolve a complicated butterfly effect... He Ju wants to change the ending of destruction, can he succeed?