To expand on the answers, C-h t opens the built in tutorial, which is good. It only covers the basics of navigation, but that's what you need to know to start. The tutorial is interactive.
Since emacs changes its behavior depending on the mode, it would be impractical to do a more in depth tutorial, in my opinion, but I liked the Mastering Emacs ebook.
One of the very best features of Emacs is it's built in help system, faster, more convenient and more accurate than most program wikis or on-line documentation.
Emacs is too big to learn every one of the 7000 or so functions, one learns just what's useful in a particular realm. Anytime it's necessary to wander into new territory, there is really good built-in help system available. Help commands start with Ctrl-h. The next keystroke determines the kind of help that comes next.
A handy prompt after Ctrl-h suggests typing '?' for additional options. The basics options are:
a PATTERN -- show commands whose name matches PATTERN
d PATTERN -- show commands whose documentation has a match to PATTERN
f -- documentation of a particular function
c -- what command runs for a particular Emacs key sequence
t -- learn by doing tutorial.
There is a full page of other help options including access to the full emacs manual.
The only gripe I have with emacs help, is that it does require some basic skill to use it. The help opens in a window in the existing frame and you need to know how to jump back and forth and close. It's a bit like having to drive yourself to your learning to drive lessons. But once you've done the built in tutorial a few times, you should have that basic skill.
The emacs tutorial: ”Just type shit. Seriously. It’s a text editor. It works like you think it should. No autistic screeching required to enable edit mode to actually, you know, edit fucking text in a fucking text editor.”
Good heavens, you've managed to imbue a classic editor flamewar comment with a surprising extra dose of incivility. This violates the guidelines, so please don't post like this again.
Since emacs changes its behavior depending on the mode, it would be impractical to do a more in depth tutorial, in my opinion, but I liked the Mastering Emacs ebook.