Question about router setup to get Wi-fi

[C O Y O T E]

Couldn't shape my title better.

Anyway, at my household we have a regular cable-based internet. Every computer is hooked up to the router with a cable.
What I was wondering was, in order to get wifi (because we also have phones and tablets), is it as easy as doing this?

[t]http://i.imgur.com/RjKh4Py.png[/t]

I usually figure how electronics work relatively fine, but I'd rather not spend money on a wireless router only to have it not work. :v:

So yeah, help?

[sloppy_joes]

Is the router you have labeled down the router/modem combo given to you by your ISP?

[editline]1st April 2014[/editline]

Also, that should work by the way.

[C O Y O T E]

[QUOTE=sloppy_joes;44420944]Is the router you have labeled down the router/modem combo given to you by your ISP?[/QUOTE]

Yes it is. The Wi-Fi one would be bought from a store probably.