An FPV system consists of a camera, a transmitter and an antenna. The transmitter sends a signal on a set channel (you can generally set this on the transmitters somehow) and the goggles can pick up the signal. In short, you can pretty much use most cameras with most goggles so the answer to "What camera does it hook up to?" is going to be "Lots of them."
You can even use multiple receivers getting the same signal. We've had two goggles AND a tablet (with a USB receiver on it) all receiving the same signal from one of our planes once, which is nice if you want to let friends see what you are seeing WHILE you are flying.
This link explains some of the info you'll need. You can skip past the "drone" part and just read the FPV bits...
This FPV Beginner Guide will teach you everything you need to know about Drone Racing. FPV or First Person View is the most unique experience of interacting with your aircraft through a level of immersion that is unparalleled by anything short of virtual reality.
www.getfpv.com
.