These resource packs are required for game play as the datapacks rely on them.
There is also a folder of client sided mods for fabric which i believe make the game better and more fun. (They also improve your machines performance and graphics).
Step by step
First press win + r to open run
Then type in %appdata%
Go to .minecraft then resourcepacks
Download the contents of the folder names 'rp for ben'
Once they have downloaded, drag and drop the files into the resourcepacks folder
Now when you start minecraft and join the server, apply the resource pack
