Is there a way to show if I have more than one Google Chrome window open in the Dock? Yes, I know I can use tabs, but there are times where I will need to open a new Google Chrome window. Unfortunately, I have bad memory and I always forget that I have a second Chrome window opened.

In Windows 10, the taskbar will show you if you have two Chrome windows open, which appears like this

.

Is there a way macOS can notify me if I have two of the same apps open?
You can right click/control click on an app's icon in the Dock to determine the number of open windows for the app. Here's a screenshot from a Google Chrome session:



A list of all the open windows for the app are shown at the top in the context menu presented on right clicking/control clicking.