How do I get rid of the backing track?

Hello, Hope some kind soul can help me out. No jargon please as I don’t understand any of it. I am trying to do the following:

  1. I am sent a backing track from a musican friend - mp3 or WAV
  2. I am to sing along with it as a guide, then send my vocals back to her to mix.
  3. When I try to do this, the backing track and my vocals automatically mix, no matter what I do.
  4. I have done the following:
  • muted the backing track
  • deleted the backing track
  • selected the singing and tried to export it as selected audio
  • cut and pasted my vocals into a new file
    How can I get rid of the music please?
    I have looked for hours on youtube and in the manuel trying to do this and am at my wits end. I don’t need how to know anything else, as I won’t be doing it. Just need my vocals on their own.
    Thanks in advance for any assistance.
    Rainie

If the unwanted music is faint & tinny it could be headphone bleed
https://www.youtube.com/results?search_query=headphone+bleed