For manual settings, it might seem a bit overwhelming at first, but I think the easiest way to explain and learn it is: Each material is going to vary so make sure you have some extra to test on. Many ways to test, but @evansd2 has provided a really good starting place with the thread linked below. Personally, I modify this one a bit depending on my project, but it’s the best way to see what settings will work best for each project.
Also, keep notes and a spreadsheet on settings-I have a spreadsheet with settings and notes for most of my ‘larger’ projects and as you build this up you’ll learn stuff too.