Hello George
This is one of the few areas Windev may not provide all the features you expect - I speak only up to version 12 as it may have changed in the new v14.
Menus must be predefined, although if you do not need too many you can do some sleight of hand and hide and unhide predefined menus to suit specific needs.
If you are looking at it from a user security perspective then the hide/unhide of menu options can be handled easily by the inbuilt groupware.
The main menu in any window can be added from the window editor.
Windows > Main menu will add a menu bar to the top of the current window
Regards
Al