How to activate a menu item of an element of the bar menu

Questions & Suggestions
2

Hi.
I just read several posts on the subject
(especially: OS X Accessibility Inspector (UIElementInspector) Tool for UI Scripting)
But as we say in French: "J'y perds mon latin" ... :flushed:

How to find information about menu bar # and menu bar item #
in the case of an application residing in the menu bar.
It is really not clear to me.
Thanks in advance