Missing Home Screen apps

There's no way to know what if anything went there if you don't remember. There is no list of apps previously on a Home Screen.

All you can do is check your App Library and see if something there reminds you of what could have been there.

Not sure what you mean.

If you noticed it was missing, then you already know what it is. Is that not so?

Are you saying you just have an empty space, but don't remember what app went there?

You can find all your installed apps in the App Library, by swiping all the way to the right most screen.

click here ➜ Organize the Home Screen and App Library on your iPhone - Apple Support