Use of tv channel 3 or 4

You either have to choose either 3 or 4 or - instead of connecting to your TV through its tuner, go directly to the Audio/Video inputs using A/V cable (also known as RCA cable - probably has red, white, and yellow ends) Connect it from the color coded outputs on the VCR to the similar inputs on the TV. The TV may have several sets to choose from. Take you choice, but set the TV's input selector to this same designation when you want to watch the VCR. Sometimes its is called "VIDEO" sometimes A/V, sometimes "AUX"