I can't find a Specific app on my iPad.
It's installed and working when I used Appstore update, but it's not visible on any of the desktop views.
iOS version is 15.1 and had same problem in iOS 14.
Search for the App using the App Library:
Use the App Library and Home Screen to organize your iPad apps - Apple Support
Alternatively, use the built-in search feature. Swipe downwards on a empty area of any Home Screen to reveal the Search dialogue - then enter the name of the App.