Could you please help me reverse the volume?

[Trebor]

… the effect I am looking for needs to reverse the direction while preserving instruments …
… like the instrumental still sound normal/forward, but notes are played reversed …

To play notes in reverse order, but not have them sound backwards, you need MIDI …

Use Reversed MIDI To Make New Chord Progressions in Logic X

Audacity only has limited support for MIDI … Missing features - Audacity Support