In the engine compartment there is a box with a lid that pops up with a set of relays and major and minor fuses and relays. There should be a schematic or list of what is what that each fuse or relay in the box does. If your truck has an empty slot for a relay or fuse in the slot marked "fog lights" you can get a relay for under twenty bucks to plug in there. If there already is one there cool, then do a test to see if there is power at the pigtails behind your bumper. A simple continuity tester, the inexpensive probe with a grounding clip and point with a light in it will work just fine. If your bumper does not have a valance on it with mounting holes built in for fog lights you can get one from many online suppliers or local auto parts stores. Shop around and you should be able to get one that fits your truck. Another thing, at least on my Ranger, is a button on the dash for turning the lights on and off. It needs to be set in the on position for the lights to work at all. When on the fog lights should come on when you turn your light switch parking lights and when on low beams. I hope this helps you figure your next steps in your project.
R