I am making a game with HTML5 and JavaScript.
How could I play game audio via JavaScript?
You can use Web Audio API for playing sounds. There are quite some audio libraries out there like howler.js, soundjs etc. If you don't worry about old browsers then you can also check on http://musquitojs.com/. It provides a simple API to create and play sounds.
For example, to play a sound all you've to do is.
import $buzz from 'musquito';
const buzz = $buzz('gunfire.mp3');
buzz.play();
The library also supports Audio Sprites.