How do I display stop, pause, play and rewind audio file controls on my iMac?
There is nothing specifically built in to the macOS that allow the keyboard to control audio file (Music, voice notes, etc.) on the Mac.

Normally music and voice notes sync with and play in iTunes. And in iTunes you can select a song and tap the spacebar to play and pause but to move back and forth in the song or audio file you must use your mouse to move around in the file by clicking before or after the moving play indicator. You can also drag the play indicator back and forth to control where you want to play from.

But neither iTunes nor Quicktime player (seem to) allow the keyboard to control skipping forward or backwards in a song or other audio file.

If that does not answer your question you may need to give us a specific use case and how you would like to control playback. There are quite a number of audio playback and editing applications out there and they all have different controls.