Now we will figure out method that help you keep all the Windows when you close an App on your Mac. Let look at the following steps:
Step 1: The first step is to Select Apple Menu and then choose System Preferences.
Step 2: Next, Click on General.
Step 3: Afterwards, Find Close windows when quitting an app.
Keep Close windows when quitting an app off to retain all windows and vice versa.
Further Note: If option Close windows when quitting an app is checked, you should press Command-Q or choose [Program name] and then Quit to close all windows as close app.
If this option is unchecked, relaunch the compatible app to retain all the windows.