How do I

I am going for the award for dumbest question asked.

I have looked for it here but found nothing that answers my specific question.

Q: Is there a way to change the color, width, or boldness of the camera view outline dotted line box on the layout?

I am aware that it is simply a guide of the scene view, however, if I am building a non-moving camera layout for an app is there a way outside filling the inner area with a colored sprite rectangle or background to make it easier to see for UI layout?

I don't think this is possible. Going back to your solution; make a new layer for it at the top, and lock it so it isn't selectable, and just delete it when your done with it