[bangonkeyboard]

It does not support it. Here are the Settings of an older iPad model to the left of the latest iPad Air's: https://i.imgur.com/YaW0eeP.png

Apple repeatedly notes that only certain models support split keyboard (https://support.apple.com/guide/ipad/move-the-onscreen-keybo...). This page was even renamed since iOS 16 from "Use a split keyboard" (https://support.apple.com/guide/ipad/use-a-split-keyboard-ip...), the screenshot of a split keyboard was replaced with a floating one, and the legacy split keyboard information was moved to the bottom of the page.