You can learn about the terminal by using Linux; you can't access it unless you're on Linux, right? And then you'll learn how your Linux works by using the terminal. I don't know exactly what you mean but if I'm understandig right, you want to learn some basic commands? Then I'd recommend this book which is great http://www.linuxzasve.com/preuzimanje/TLCL-09.12.pdf Want to learn about Linux system file structure? Check this sitecan I use the terminal for learning Linux?