Your FPV camera has a built-in transmitter that will broadcast a video signal to the monitor, which has a built-in receiver. Open your FPV monitor box and pull out the components shown in the photo below.
WarningBe sure to attach the both antennas to the FPV monitor before powering it. Otherwise you run the risk of burning out the receiver.
FPV monitor and built-in receiver
The video below will walk you through setting the band and channel of the transmitter and receiver.