problem recording a second track without picking up the first track

I imported my already-recorded instrumental backing track. I opened a new track. I want to play the first track, hear it (through my headphones), and record my vocal on the second track. When I try to do that, I record not only the new vocal on the second track, but the instrumentation from the first track. How can I listen to the first, and record the second track without also picking up the first track on the new second track recording? Thanks for any help.

WIndows guy here.

So it is not supposed to do that. What is your Playback Device set to? Are you somehow also playing the audio to some speakers or to your recording device ?