Tamagotchi-like minigame

Hi there,
I’m working on a horror game for a school project and I had this idea that the player can pull up a little game device that’d play a minigame like a Tamagotchi pet. This pet would directly interract with the main killer chasing the player, so I also would like to pull maybe a mood value from the minigame.
I’m honestly pretty stuck on how to start this process, though. I made some art of the game device and added it to a UI widget with some buttons to get a framework, but I’m honestly stuck on where to go from there. Any help/tips on how to get this project rolling would be amazing. Thank you!

I recommend using horror engine from the marketplace. Very easy to use.