I was confused too, but another comment here links to a video demo. That gave me enough clues to realize that you start off in a "notepat" app in this "computer." You can click "notepat" to go back to a prompt. At the prompt, you can type "list" to list all the commands. (I noticed there are aliases as well, like if you type "help" you actually go to "chat".) The demo shows a few things you can do, and probably you're meant to explore the other apps to see how things work.