Adding Background Music to a Game in Unity 2D

1. In the Hierarchy Section, right-click to bring up pop-up menu and choose Create > Audio > Audio Source.
2. In your project, create a new Folder called SoundFiles.
3. Drag a WAV or MP3 Audio clip to the SoundFiles Folder.
4. Then Drag that WAV or MP3 file from the SoundFiles Folder to the Audio Source “AudioClip” attribute. See image below.

5. Check Loop if you would like music to have it continuously play.