I uploaded this mixing tutorial to my drive which does a really good job of explaining gain staging by using LUFS as a levels guide. Its a bit old and mainly geared toward rock music but the general idea is there. A lot of the plugins in the tutorial are free plugins if you feel inclined to download and try things out:

https://drive.google.com/file/d/1CQSBifUhaklS2VMkOWGgWYdVJeh8JIwN/view?usp=drive_link

One thing I will say, don't take it as gospel. Its a pretty generic tutorial but it was how I gateway-ed into the way I mix now. There's a much better approach to mixing in LUFS that supersedes the need for all those steps. I'll be putting a video tutorial together to explain how I do it and also an overview of using a mid side mixing for mono compatibility and to get your mix to translate better. More soon!