To see the Mac desktop and the virtual machine desktop at the same time, switch to Single Window view.
In Single Window view, the virtual machine appears in a single window that you can resize and move with the mouse.
Switch to Single Window view.
In Full Screen view with the Full Screen title bar, select View > Single Window.
In Full Screen view without the Full Screen Minibar, use the keyboard shortcut +Control+F to switch to Single Window view.
In Unity view, use the keyboard shortcut +Shift+U to switch to Single Window view.