If you have audio annotation .wav files created by your camera for particular images (e.g. a.jpg and a.wav), LR will import them as a special "sidecar" files, and they will appear in the Metadata panel on the right:
Image may be NSFW.
Clik here to view.
If you click on the .wav filename, LR will play it.
If you want to import, tag, and search audio files of any other format, including audio files that aren't associated with a particular image, LR doesn't have that capability builtin. However, you could use the Any File plugin to import and manage those audio files.