Newbie installation help! (Nutone BK105 builder chime)

Hi everyone.

I just bought a Ring 2 door bell from amazon. It’s this one:

My home has a builder doorbell chime, NuTone BK105.

It was installed by the builder when I moved in. The front door button is this rounded, lighted button. I assume there’s wiring behind of it. So there’s no visible mounting screws on the button cap for me to remove. So how do I install my new Ring 2?