The command line is your friend.
For advanced users, this is an obvious statement; for the beginner, not so friendly. Where do you start with that darn blinking cursor?
How many Linux commands are there? A whole bunch. Thousands. Tens of thousands depending on dependencies and packages. But don't worry, you don't have to learn them all.
Saying or writing something original about Linux commands is a bit difficult: far smarter, folks than I have written about, compiled, and battle-tested the multiple combinations of commands available to the Linux user. And this book is not intended to be about Linux commands. So instead, I will give you a handful of basic commands that I find myself consistently using ...