Kali Basics

I have played around with Kali Linux a few times but I've gotten nowhere. I want to know how commands, when to use them and have information to be able to act on the spot not look up some script someone made. Any videos, articles, anything really that would help me on my path would be great. Also I have someone who had been harassing me and i want to see if i can frighten them, any ideas? If so tutorial??