Dragging windows between screens

I have two monitors. One is the laptop, and the other is a standalone Dell.

Dell is my primary monitor. I know this because it has my menu options on the top.

Currently, when I drag windows from the Dell to the Mac and vice versa, the windows do not scale to fit the proper screen. For example, when I drag Outlook from the Dell to the Mac, it appears the same size on the Mac and doesn't adjust to fit the smaller screen. I would like to know if there's a way to make the windows fit to scale. Help?

Thank you