Some trucks are fully pre-wired while others are only partly wired & I've heard some that had no fog switch wiring at all.
If you have the plugs behind the bumper for the lights as well as the 4 pin connector for the switch behind the radio bezel, you MAY be fully pre-wired & all you'd need to do is install a relay or fuse, add the lights & radio bezel with a fog switch opening.
If you have a service manual or can find the info here on the forum as to the location of the relays in the underhood relay boxes, you can see if you have the relay installed of if you need to add one.
On the other hand, I've heard guys who have that setup & no matter what they did, couldn't get their lights to work.
If you aren't able to get the oem wiring to work, I do a conversion kit that allows you to use the factory switch (old style see pic below) to control pretty much any 12v light or accessory by bypassing all the factory wiring.
Several of the guys in the Ranger community are running my fog conversion kits... heck, I have 4 of them in my Ranger.
An advantage of the kit is it will allow you to control your lights whenever you want, not just with the headlights on... you can run the fogs by themself, with the parking lights, with the low beams, with the high beams... whatever you want.
Hope that helps.