Be careful which Clock App you download from the Google Play Store. I was trying to find one that would give me a digital clock and alarm for a desktop clock. The one I downloaded had Clock Launcher attached. Once it downloaded my home all the apps on my Home Screen vanished except for the time widget at the top and the search bar at the bottom. When swiping left, all of the apps were gone. I did a restore from the Samsung cloud and got the apps back but then the phone worked like an iPhone and I had to swipe up to see them. I couldn't move the time widget on the search bar on the home page.
I was able to uninstall the Clock app I downloaded, but the launcher remained. After trying almost everything, I was only able to uninstall it by finding it on the Google Play Store and uninstalling it there.
You downloaded a custom launcher. They are alternatives to OneUI home, the default launcher. You didn't lose anything the new launcher just didn't know your preferences of where you want your apps on your home page.
If you download another launcher and want to go back to what you currently have: settings - apps - choose default apps - home app
