Count/Measure reactions

I wanted to create a simple interface that changes colour constantly. When the user sees a face between colours I want them to hit any key. At the end I want to display how many images of a face were displayed and how many times they hit a key. Has anyone tried somthing like that before and got any tips or tricks on how to tackle this on Captivate 2019 (mac)

Thanks in advance for any thoughts!

Andy