Type C-h t to invoke the self-paced tutorial. Just typing C-h enters the help system. The tutorial is available in many foreign languages such as French, German, Japanese, Russian, etc. Use M-x help-with-tutorial-spec-language RET to choose your language and start the tutorial.
Your system administrator may have changed C-h to act like DEL to deal with local keyboards. You can use M-x help-for-help instead to invoke help. To discover what key (if any) invokes help on your system, type M-x where-is RET help-for-help RET. This will print a comma-separated list of key sequences in the echo area. Ignore the last character in each key sequence listed. Each of the resulting key sequences (e.g., F1 is common) invokes help.
Emacs help works best if it is invoked by a single key whose value
should be stored in the variable help-char.
Some Emacs slides and tutorials can be found at http://web.psung.name/emacs/.