Yamaha s90 KeyBed to Midi-Controller?

Hi I have the KeyBoard Assembly and contact board from a Yamaha S90. I’m interested in using it to create a simple midi-controller(midi or USB). I’m pretty new to this, I’m hoping someone could point me in the direction of an encoder or additional parts to get started. If you know of a beginner’s resources that would be much appreciated as well. Thank you for your time.

The parts number for the keybed is V6469500.