I'm getting a corrupted firmware error when trying to restore my iPad. Where can i find iPad firmware?

Restoring your iPad to Factory Settings will re-install the most recent version of iOS/iPadOS supported by your iPad.

Restore your iPhone, iPad, or iPod to factory settings - Apple Support

All System Updates are digitally signed by Apple - and can only be installed whilst the digital signatures remain valid. After release of a new iOS/iPadOS version, the immediately preceding version continues to be digitally signed by Apple - however, usually within a few days, Apple will revoke the digital certificate with which the earlier version is signed.

Ensure that your Windows PC or Mac computer have been updated to the most recent version of iTunes or Finder - as appropriate for the computer. The current version of iTunes for Windows requires Windows 10 or Windows 11.

If you continue to experience difficulties, you might be best advised to seek assistance directly from from Apple Support. You can contact the Support Team using the Get Support link at top-right of this page. Alternatively, if you have access to another Apple device, you can initiate and manage your support cases using the excellent Apple Support App. If not already installed, 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 provide assistance:

Genius Bar Reservation and Apple Support Options - Apple