Can I build a Sound Organ with an old PC WIN XP?

I’ve saved an old PC for years hoping I could use it later to build something I know nothing about…
I want a sound organ for my outdoor garden…
But I want it to come on when a human sensor activates…

Could you explain a little further what it is you’re trying to accomplish? “Sound organ” as in dynamically powering lights reflective of human vocal activity, or playing actual samples of a pipe organ when someone walks by? Not sure what you mean.