Best way to use a RPi as a speaker?

I have an RPi3 hooked to a decent speaker which I use to stream music to.
I’m using the headphones jack but I’m quite happy with the sound.
It is running raspbian bullseye and is regularly being updated.
What would be the best way to use it as a Home Assistant media player?
I’d really like to be able to get advantage of i.e. media browser, TTS, etc.