There are a few reasons why you might not be able to turn off private browsing on your iPad.
You may have accidentally enabled Guided Access, which prevents you from changing certain settings.
You may have restrictions enabled on your iPad that prevent you from changing certain settings.
You may be using a third-party browser that doesn’t support private browsing.
If you’re unable to turn off private browsing, you can try the following
Check to see if Guided Access is enabled. To do this, open the Settings app and tap on Accessibility. Then, tap on Guided Access and make sure that the switch is turned off.
Check to see if restrictions are enabled. To do this, open the Settings app and tap on General. Then, tap on Restrictions and make sure that the switch is turned off.
Try using a different browser. If you’re using a third-party browser, try switching to the built-in Safari browser.