It's the End of the World, Why Don't You Just Eat and Wait to Die?

Life in another world seems not as beautiful as the rumors; mother's abnormality, fire at home, being locked in a small dark room, struggling to survive; Escape from the shackles, but unexpectedly the world outside is rampant with zombies. How does a child's body survive in this chaotic world? It's the end of the world, why are we still eating and waiting to die?