@johnbhoy1967 This is just the way Roku built devices work. The apps you install are account based, rather than device based. Therefore, if you install on one device, the app will automatically install on all your other devices. Similarly, as you have found, deleting from one deletes from all others.
There may, however, be a setting somewhere that isolates one device from the other.
Apple devices do the same thing, but at least there you can turn off auto-sync via the icloud settings.