Certainly not the recommended way to remove a program.
Normally you use Programs and Features and select the Program from there to remove it or,
Use Revo Uninstaller: https://www.revouninstaller.com/revo_uninstaller_free_download.html
You also need to stop Greenshot via Task Manager prior to uninstalling it.
In the latest version of Windows 10, you can reach all of the installed programs and Apps via Apps and Features.
(Right click on the start menu)
