Last point first...
Apple does not supply iPad internal components or batteries for self-repair. Apple similarly does not supply OEM components outside of its network of Apple Authorised Service Providers. If you attempt to use a third-party battery, you may disable some iPad functions - and at the very least will void your warranty and forfeit any future support for your iPad.
The battery health feature is exclusive to iOS for iPhone. iOS/iPadOS for iPad has never had the Battery Health feature - most likely because iPad batteries are both considerably larger and have a much longer service life.
An iPad battery is rated to maintain at least 80% of its initial capacity after 1000 full charge/discharge cycles - whereas an iPhone is rated to have 80% of initial capacity after 500 full cycles.
Using unsupported methods to access the battery cycle count or estimate battery health - such as using third-party Shortcuts to read data from Analytics files - may at best be unreliable, if they work at all. System software updates may change the format and content of Analytics data, requiring appropriate update of associated Shortcuts.
There are however third-party software packages for Windows PC and Mac that can access battery cycle count. Popular choices for Mac are Coconut Battery and iMazing - whereas iMazing is available for PC.
https://www.coconut-flavour.com/coconutbattery/
If you suspect a problem, or experience difficulties with your iPad, you would be best advised to seek assistance directly from Apple Support. 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 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
