All of these tutorials assume you have knowledge of Python and Sims 4 XML structure. Check out Coding 101 if you don't know or need a refresher.
Triplis - Injecting to Test Autonomous
Frankk - Automatically Assign Traits to Sims (Sims 4 Script Modding)
MizoreYukii - How to Create Custom Occult Rings & Plumbobs
MizoreYukii - Setup for UI Editing
MizoreYukii - How to Shrink World Icons on the Selection Screen