I don't know if this is where I should ask beginner technical questions. When I select primitives (faces), there are 2 different indications, the faces I've moused over in orange and adjacent areas that are in grey. What is the grey indicating?

If you are talking about this then it's a primitive which is on the backside of the object. To select only visible geometry, which is in front of the camera, then press Shift+V as a shortcut when you are in Selection mode.

Thanks! That seems to be it.

kenned-doll
I don't know if this is where I should ask beginner technical questions.

When it comes to grey area, there are no beginner questions