iPad with 9.3.5 can’t load kindle

Sorry, but the Kindle app requires iPadOS 15 or later, and if your iPad is still on iOS 9.3.5, it's much too old to be able to run the Kindle app now. You might be able to read Kindle books via Amazon's web interface, though.

Regards.

The Kindle app requires iPad OS 15 or greater. I'm afraid the only solution would be to purchase a new iPad. It won't work on yours.