Saving Civilization from Scratch

Brother, I just went on an extraterrestrial exploration, how could I become the last survivor of mankind? . . . . . The Holy Crystal was sealed again. Last time, we gathered the power of all mankind to break the seal. But this time, there is only one of our teams. But I want to save my home, even if it costs my life, I will break the seal! This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.