Do not use the Essential Mod
The Essential Mod1, not to be confused with the Essentials Plugin2 or its updated Fork EssentialsX3, is a mod that tries to be a all-in-one solution for players similar to what you imagine with Mods like LabyMod4 or the 5zig Reborn5 Mod.
The issue here is, that it has a lot of problems, making it a worse mod and not really a good choice to begin with. This post will cover all the points I managed to gather from the community over the years I've heard of this mod. Enjoy.