Harmony vox

Brand new on this forum, looking for help with a problem. I have some harmony tracks I would like to replace with my own vocals. Is there a facility on audacity or any other software that allows me to do this, say by singing the first note so that the remainder of the file is replaced automatically please?

If you have a recording of one voice singing, you could duplicate the track and then pitch shift the duplicate. That will give a simple form of harmonization (“parallel interval”), but note that pitch shifting a voice by more than a small interval can sound unnatural.