Is there is website that explains the game mechanics for Skyrim

You can access the manual in steam. To do so go to your library of games and single click on "TheElder Scrolls V: Skyrim" in the left hand list. That should bring up a page for Skyrim. You can then click on the [Manual] link on the right side of the page (under [LINKS]). This isn't very obvious so post if you have any trouble finding it.

You can also find good information on general game play by reading the Elder scrolls wiki, Skyrim on Wikia, IGN guide, here on stack exchange and by googling for "skyrim beginners guide" or something similar.

The steam manual is available via a simple link, but I have not included it here as I don't want to support use of non-purchased copies (by people who might find this while searching for the manual). I believe all valid copies of the game should have access to it through their steam client (it uses Steam on PC) or physical copy for consoles/in store purchase.