How do you organize BIOS files on Android?

Hi everyone, I recently got my first Android handheld, an Ayaneo Pocket Micro. I followed TechDweeb's guide to set it up, but I'm unsure about the BIOS part that he doesn't cover. Most other stuff (ES, RA, standalones, etc...) is already set up and working fine.

I already went to the Megathread > BIOS Files > Retroarch System Files (BIOS/Firmwares/OS) and downloaded everything in there. I extracted all the zips and moved them to a BIOS folder that I created on my SD card.

Thing is, many of the systems have multiple BIOS versions and other files in the respective folders. Should I keep the original folder structure, or should I pull out all the files in the main BIOS directory? Also, since there are some zipped archives in there, should I extract those as well?