Welcome Clive. Don't worry about the photo, everyone seems to struggle with getting them attached to begin with.
For flashing lights, for a few quid
you can have four. But you want to switch them from your transmitter, so you will either need a servo to flick the switch on and off (very old school) or an
electronic switch like this. It plugs into your receiver and if you have a switched channel on your transmitter (that is, one that is operated by a switch, not by the joysticks) then that is the channel to use. It is connected between the battery and the lights, and you are all set.
Don't worry about asking questions if that still doesn't answer your query. We all started knowing nothing. Well, I did anyway.
Greg