Do you have to use radio in car to listen to movies?my car has no radio

You can use your radio or the pole speakers that they have.

You can and I also have speakers as well so you could do both if you want to

No they have speakers that play the movie they hang on your car window

They have the old fashioned drive-in speakers but the sound is terrible. We sit outside the car and just take a small portable radio. That's what most people do.