Doomsday Attack

The end of the world suddenly comes, where is the system? What about special functions? Why don't I have one! Before the end of the world, our male protagonist Zhou Zhen's dream changes every day. Today he wants to be a soldier king, and tomorrow he wants to be a boxing champion. But one thing has never changed, and that is that he insists on exercising every day and pushes his body to the limit every time, so he has superhuman physical fitness. All useful people will be taken into my sanctuary! Let's see how our hero makes his way in the apocalypse! This is my first time writing for a newcomer. If you don't like it, don't touch it. I hope you guys can give me some advice. This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.