Hi Steven, welcome to the forum.
I don’t have a computer in front of me, but the basic steps to get you going could be something like:
Audio device in chop, select your device, in your case the computer microphone.
Analize chop, set to RMS.
(you can also branch out here with a trail chop here to see the values “over time” that you are dealing with)
Math chop, to scale this value to whichever range is useful to your project /idea.
Null chop, it’s often a good programming habit to add a null at the end of an operation, it will make adding nodes in your chain much faster. (in fact you might need to add a limit chop set to clamp to keep the value within a certain range i.e. between 0 and 1, and perhaps also a lag chop to smooth the incoming value a bit).
In that null you should see a value that responds to your microphone. Reference that value to whichever top and top parameter you intend to use. Try for example to change the colour of a constant top. (make the null active by selecting it and pressing ‘a’ on your keyboard, and drag and drop the null onto the constant top RGB parameters)
I hope this helps!