2007 Mazda 3i

my car did not come with fog lights and I am looking into adding them.
I checked under the bumber and the wiring harness has the connectors for the fog lights. Also, in the fuse panel under the hood, there is a relay in the fog light spot.

Could I just buy lights, hook them up and install the light switch with the button for the fog light and be good?

I saw kits that had wires that needed to be run through the firewall, with grounds, wires that needed to be hot-wired to the ignition switch and so on, but I really don't want to go that route if i don't have to.

So bottom line - can I just install a new OEM light switch (with fog light capability), and fog lights and be good - or is that not possible?