how to use blender add-ons once they are installed

I installed an add-on called Instant Meshes Remesh and when I try to use it, I either get a error or nothing happens.

I can find plenty of videos and tutorials on how to install add-ons, but none of them actually show the process of using them.

I am just trying to retopologize a super dense mesh to something workable for animations and games, am I skipping steps?