Media Server

Soon to be a new NAS owner and user of Unraid and as the title says my first use will be as a media server using the Ugreen 4800+ with the 'arrs. I will be starting with 2 x 12tb hdd and 2 x 2? tb nvme drives for cache (pool?). I want to use 1 nvme for downloads and 1 for app data etc. I have watched Spaceinvader1 video where he describes exactly this.

First question is the video was done with 6.9. Has anything changed with 7.0 that i should know? Second is what file system do I use? Also if anyone has any suggestions for this setup feel free to share. Thanks in advance.

EDIT: Originally was getting confused by the term SHARES. Am I wrong in assuming this is just another term for FOLDERS?