I'll teach you about 4 topics
Kali-Linux, Java, Python and android hacking.
Kali-Linux it is OS used for hacking.
Java is a programming language based on principal of OOP's. It is the most common language used now are days for game development, web programming.
Python is an interpreted, high-level, general-purpose programming language. Created by Guido van Rossum and first released in 1991, Python's design philosophy emphasizes code readability with its notable use of significant whitespace. With ease you will be able to master them.
Introduction to Android Hacking applications,tools and resources, and securing your device from getting hacked.
HOPE YOU ENJOY.