This tutorial will cover how to add audio to your timeline in Unity. First create an empty GameObject to hold your audio. Then create two more empty GameObjects, one for your voice over and another for the music. Then give these two new GameObjects each an Audio Source.
Next, create two Audio Tracks in your Timeline, one for the voice over and one for music. Put your matching GameObjects into the tracks and put your actual audio clips in the play area of the Timeline.
To help your Timeline not get cluttered you can create a Track Group and then put your Audio Tracks in it.
With your audio in your Timeline you can now fine tune your camera cuts.