An iPad may become warm when in use - warming perhaps being localised to a specific area. While the iPad may become warm, it should never become too hot to handle.
If you are using an iPad is high ambient temperatures, the iPad’s thermal management may automatically reduce screen brightness, reduce performance, or may switch-off entirely to protect the iPad and its battery from damage. Removing the iPad from a fitted case, if used, can aid cooling.
If your iPhone, iPad, or iPod touch gets too hot or too cold - Apple Support
Should you have any concerns, consider seeking advice directly from Apple support. You can contact the Support Team using the Get Support link at top-right of this page. Alternatively, you can initiate and manage your support cases using the excellent Apple Support App. If not already installed on your iPad, the App can be downloaded from the App Store:
https://apps.apple.com/gb/app/apple-support/id1130498044
You might also visit the Genius Bar at your local Apple Store or Apple Authorised Service Provider (AASP) - where the technicians will be able to test and assess your iPad:
Genius Bar Reservation and Apple Support Options - Apple