Tips to study vuforia’s image trackers

Hi! My name is Bruno and I am a Brazilian software engineer student. I started to study unity and vuforia because I want to do a simply project, but I am a begginer and I don’t where to find good content to study! If you guys have any tips I would really apreciate! I want to learn mainly how to deal with image trackers!

In my project i want to have 3 image trackers, if image tracker A and B are showing in the AR camera, and image tracker C  is  also showing, image tracker c will show a 3D figure. Any tips?

Thank you very much!!