My personal configuration for neovim I will do my best to comment the configuration file. Feel free to crib/steal this for your own personal use.
Run ./install.sh to link the configuration files to the proper location
When you open nvim for the first time, packer should install itself. If it doesn't, please consult their page for instructions.
Then :PackerSync should get the plugins to install. Follow instructions for their page for how to use it.
Finally, there are some language servers to install. Instructions are in the lua/plugin/lsp.lua file.
Also, consult the official neovim page on usage instructions as well.