Image occlusion enhanced question

what is the first field in the image occlusion enhanced? so I can finish my add card and also where can i find a beginner lesson for how to use it

I think, you’re already figured out how to use it, but just in case, the AnkiWeb page says that

The use of this add-on is detailed in the Wiki and a series of video tutorials on YouTube. Please note that most of these resources have yet to be updated for Anki 2.1, and as such might not cover recent releases of the add-on fully.