i just found the "Flat Earth Society" and I know you guys are sick of globe-rs like me but I don't know how to get info on some of my questions any other way but to go to the source

So my first question is about how the phases of the moon because the map i have studied had the sun acting as a spotlight rotating above the earth and I'm not sure how
1. the moon creates light and
2. how the phases of the moon are created especially the circular "shadow" on the moon
also
3. are there any large/popular "facts" that the society does not believe in?
I want to have civil discussions and I want to understand this movement so these are some of the big problems I have and I want to get them out of the way.