I Have a System in the Zombie Apocalypse

(System-focused + female lead + characters don't lose their intelligence + few tearjerkers) This is the first novel I've ever written, and I did it purely as a hobby, so it probably won't be very good. I hope you'll share your thoughts and give me some advice.

The apocalypse arrives, and a System falls into his hands. Bei Guchen sets out on the path to leveling up with his girlfriend An Mumu and their companions. But later, he discovers that things aren't so simple. The zombies didn't come without a reason; there is a conspiracy behind it all...