Thanks for your feedback Paul, appreciate it.
What I’m trying to do is illustrated in this video below:
Trace an image using a vector pen (result can be seen at 13:40). The problem with your suggestion is that these would be filled immediately and you loose the underlying detail of the image you are tracing.
Then create individual shapes that can be colored in (can be seen at 21:45)
So In my simplified example, I have a shape that is closed and I was expecting that the Divide geometry option would result in a tail shape, a body shape, an eye shape and a remainder part outside the fish. Instead, the Divide is giving me all these shapes and I have not found any explanation for this.