Remove automatic app grouping on iPad

The automatic app grouping only occurs in the App Library, the last page of the Home Screen. There are no settings or ways to modify the presentation of the App Library.

Otherwise you are free to group (or not) or move apps on the Home Screen: Move apps and widgets on the iPad Home Screen - Apple Support.

Perhaps you refer to your iPhone's App Library - and its organisation of Apps into categories...

The App Library sorts your installed Apps into multiple automatically curated App-groups - based upon App category information derived from the Apple App Store.

While the App Library cannot be directly edited, you can create App Groups of your own choice on any Home Page - this being fully described in the iPhone User Guide:

Organize your apps in folders on iPhone - Apple Support

More information about the iPad App Library are organisation of your Home Screens can be found here:

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