I want to power a light from the pwer coming off a plug, plu sinstall a switch for the on/off. Can this be done

By plug do you mean a plug or an outlet where a plug goes? The simple answer is yes. However, have you ever wired a wall switch or light? Are you comfortable pulling wire and installing wall and ceiling boxes? Do you know what wires go where? Get back to us if you think you can do this by yourself.

This is simple for someone who understands what they're doing... but dangerous if you don't!. think twice... PLEASE

This can be done if you can get a cable from the receptacle to where you want the light and a cable from the light to where you want the switch. It can also be done if you can get a cable from the receptacle to the switch and from there to where you want the light.

If you mean you want to plug a lamp in the receptacle and control it from a switch, this can be done if you can get a cable from the receptacle to where you want the switch.

You can buy cord switches just for this application. Some splice easily into ZIP cord.

If it is that you just want to turn a lamp on and off, you can probably find a wall mounted remote control switch.