If you'd like to view, or delete only some of your themepacks, click on Start > Settings > Personalization > Themes.
You can delete them from File Explorer or use Windows Settings. Microsoft stores all the themepacks in two folders to show the list and save the files.
In this tutorial, we show you how to view and remove all of your installed themepacks. Microsoft has installed Themes for Windows 7, 8, 8.1, and 10 more easily than ever by using themepacks.