I will be the first to admit that this will not be a perfect solution, but you might want to check out a program named FaceCam Cover (v1.04 11/28/2018). I found it at:
https://www.portablefreeware.com/forums ... 07&p=91515. Look in the ini file to find the options for displaying and/or hiding menus and options to make changing the settings a little harder. Once you get the ini set the way you want, set the ini file as read only to 'kind of' lock the settings from being changed easily. The program only hides one 'area', so you can make a copy of the program folder (very small) and launch multiple instances of the program to hide multiple areas on the screen.