Could I use this transmitter and receiver to transmit video?
If so, what camera can I use?
Any kind with a compatible cable connector.
Also how could I hook a batter yup to it instead of using the wall transformer
Measure the voltage of the wall transformer, then use a battery of the same voltage. You can probably even use a lower voltage. Just cut the power supply wire and attach a battery plug to that wire.
You will also need a TV to view the images, or an adapter that lets you view the video by USB to your computer.