Here are my notes I made while reading the book Head First Design Patterns. It has a full and quality implementation of every design pattern in the book with notes on different patterns and principles. The examples are written in Kotlin.
The Head First Design Pattern is a great read if you are just starting to learn design patterns.
Check out the Github repo below and do star it if you find it useful: https://github.com/Devansh-Maurya/Design-Patterns-And-Principles