iPad stuck on strange screen after powering on

An OS corruption can lead to a non-bootable device as you describe. Without diagnostics, it is impossible to attribute an explanation as to what may have triggered the issue.

Restoring the device, which in this case entails re-installing the most recent production version of iPadOS, is normally sufficient to resolve the problem.

In the unlikely event that the problem should reoccur, you would be best advised to seek assistance directly from Apple Support - and request a remote diagnostic test of your iPad. You can contact the Support Team using the Support link at top-right or bottom-left of this page.

Alternatively, you can initiate and manage your support cases from Apple devices using the excellent Apple Support App. If not already installed, the App can be downloaded from the App Store:

https://apps.apple.com/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 the iPad. If a fault is identified, you'll be in the best possible place to explore your available options:

Genius Bar Reservation and Apple Support Options - Apple