MAIL icon in iPad screen

Move the Apple Mail app from the App Library:--> Find your apps in App Library on iPad .

Regards

Giulio

If you cannot find an installed App on one of your iPad Home Screens, you'll be able to find all Apps already installed on your iPad using the App Library and/or Spotlight Search.

To access the App Library page, simply swipe to the left from your Home Screens; the last page is the App Library. Here you will find both automatically curated App groups, an alphabetical list of installed Apps - and a Search tool.

After opening/using an App, it should be visible in Spotlight Search - unless they have been excluded in your device settings.

More information about using the App Library can be found in the respective User Guides:

Find your apps in App Library on iPad - Apple Support

Additional information for Spotlight Search can also be found in the User Guide:

Search with Spotlight on iPad - Apple Support