exFAT? I want FAT32... Help!!

Hi Jon new here to the forum. I have a MBP. I also just bought a 3TB G drive. I used to be a PC person, now I mostly use MAC but still have a need to access my files- all 2-3 TB of them- on the PC. I am a professional photographer and I have a couple of TB on G drive externals that are formatted for Macs. I want my new 3TB G Drive to have all the files that are on my G Drive externals formatted for Mac.

At the risk of being redundant, my goal is to use my new 3TB G drive in this way: hook it up to my MBP, format it in FAT32 and transfer all the files from "old" my G drive (which is formatted for Mac) to this new 3TB G Drive. I will then hook up the 3 TB G drive up to my PC as it will have all of the files that are on the Mac-formatted G drive.

The G Drive manual says to go to disk utility on the MPB, go to "erase", and then format it to FAT32. Problem is, when I open disc utility on the MBP, and I go to "erase" I am not given an option to format it in FAT32, which I have been told is what I need that 3TB drive to be so that it can work on both the Mac and PC. The only options I get are a bunch of Mac-OS ones (4 including Mac-OS, Mac -OS extended, case sensitive, etc), and then exFAT. What is this exFAT?

How do I make it to FAT32? My understanding is that FAT32 is the format I will need to do cross-operating system work, not exFAT.
I have done a little bit of research and my concern is that if I format it in exFAT my PC, which operates on Windows XP, won't be able to work with it. Plus who knows, in the future I may be using a different PC operating system and I am worried the exFAT won't work.
Any help appreciated.
Thanks!
Jon