Get sideloader, you can sideload the APK to your quest. The file is an APK so you cant run it on your pc,
To sideload it onto the quest yes you need to be plugged in. And to play no the quest has its own operating system running android meaning you can install APK's directly to your headset. Go download sidequest from http://sidequestvr.com/ , from there you can install many other games directly onto your headset from itch.io ect. Here is a tutorial for sidequest