And after than (as jrockway noted elsewhere), press Control-H i to get to the Info pages menu, which is the hypertext documentation inside Emacs. What you're looking for is almost certainly in the main Emacs section or the Emacs FAQ.
Info has its own manual, but most of what you need to know to start is that Enter visits a hyperlink (which are probably purple and/or bold), 'u' goes up one level, 'n' and 'p' go forward/backwards one node, and 's' searches. (To get a more detailed keyboard shortcut list, type "Control-h m" inside of the info buffer.)
