stylua-nvim is a minimal wrapper around the Lua code formatter, StyLua. It does pretty much what you'd expect it to do, format your Lua file using Stylua.

Make sure you have StyLua installed and then install this plugin:

use({"ckipp01/stylua-nvim"})

If you would like your plugin manager to automatically download Stylua for you, run the Stylua install command using your plugin managers hooks. For example in Packer, you can use the following:

use({"ckipp01/stylua-nvim", run = "cargo install stylua"})

Everything you need should be in the help docs.