Hey everyone,
So what I’m trying to do is to have one track of acoustic guitar that I add effects to (filter curve, compressor, etc.) and one of the following options: 1 would e another unaffected channel that can listen to as reference to my editing 2 - just a way to bypass the effects or turn them off and back on again or the same reason of having a reference.
Thanks in advance to all the answerers:)
Duplicate the track, apply effects only to one version, then toggle between them.
https://manual.audacityteam.org/man/tracks_behaviors_preferences.html
this didn’t work
What didn’t work?
Depending on what version of Audacity you’re using, you may have to change the solo-button behaviour to “Multi-track” to toggle between tracks, see … Tracks Behaviors Preferences - Audacity Manual
even after I duplicated the track, the filter curve changed on both of them. Even I opened the track in ANOTHER PROJECT
Thanks, but still every effect I add is added to both tracks.
To apply an effect to a specific track, click on “Select” at the bottom of that track’s Track Control Panel before applying the effect.
See Selecting Audio - Audacity Manual
I hope this helps. 
You don’t have a SELECT button because you have an older version of Audacity.
You can fake one by clicking just right of the up arrow.
Audacity 2.4.2 has a formal Select button down there.
Koz