Capacitive keyboard

I am looking to build something simple that I could slide under a sheet of paper with shortcuts printed on it, that would work like a sensor keypad, consisting of 120 capacitive sensor elements.

I may eventually build my own musical instrument using this technique as well.

I am looking for ways to wire everything so I can use the smallest micro-controller board with the greatest amount of capacitive sensors possible, waiting for input simultaneously, without interruptions of any kind.

What parts and what connection method/protocol should I use?
I am not a big microcontroller developer.

Thank you.
Vladimir Tolskiy