What should I install this one and not an other ?

Because is a new datapack and this datapack as been made to troll your friend, you can use that in a single player world with essential, + this will NOT show a a message when you load this!

Ok, So ,How to install it ?

just put it in the datapacks folder in your world folder! And VOILA all clear and clean.

But, What does it do ???

this datapack prevent player to separate themselves