macOS How do i connect a window via a menu or button?

[macosus]

I've just started making a program in xcode, and in interface builder, when i am making a window, i get stuck by how to connect the window. What i mean by that is that when a user selects a menu item or clicks a button, a window appears. I've been searching around the web but i am having no luck.

 

[gld13]

In IB, hold the control button and:
click on the menu item
drag your mouse to the desired window
select makeKeyAndOrderFront

Save the nib and you should be set!