How WELL do you think you know terminal commands or Linux File System ?

If you want to know even more about how Linux is structured and what each of /home, /var, /etc .. directories are, you can take a look at this link right here explaining Linux Files Tree and discussing about each directory a little bit.

https://www.linux.com/training-tutorials/linux-filesystem-explained/

Another thing you might want to learn is different terminal commands. Even though we covered some of them and we will cover even more throughout the course it is still good to practice all of the things we covered in this section and perhaps learn 1 or 2 new commands! Remember, terminal is THE MOST IMPORTANT tool that you will use as a penetration tester!

https://ubuntu.com/tutorials/command-line-for-beginners#1-overview