How to properly attach events in GTK3+?

Question

GTK+

There is a Notebook
in which the Grid is located,
in which Buttons are located,
in which a Menu is called on click,
in which, on a click on the MenuItem, an event should fire that adds a new page to the Notebook.
Each element is a separate structure in its package.
In order to bind an event with the Connect() method, you need a live widget. Those. I need to either throw a Notebook to the Menu, or throw a Menu to the Notebook. Neither option suits me.
How to solve this problem correctly?