In order to become a “hacker”, preferably white hat (the good guys), you need to learn:
- Windows systems and how the work
- Linux Systems and how they work
- Basic Web transactions (HTTP Get, Post, etc)
- Security concepts
- Command line skills for Windows and Linux
- Basic bat/bash scripting skills.
- Lots of others, but that should get you started.
You can get started with all the skills just follow the blogs of edureka:
What is Ethical Hacking? - Edureka
You can search out for tons of tutorials on edureka: