About the WebGL audio issue:
See if googling "No sound in Unity WebGL build - Unity - FMOD Forums" helps.
If not, I heard something about browsers no longer being able to autoplay audio (unrequested audio being blocked). Maybe a mute/unmute button would fix that, or having the audio start off by default and a button to enable it as the game starts like may games do. If none of those solve it, then idk either.