How can I cut off private browsing in Safari for my iPad???

Private Browsing is an integral feature of Safari. While the feature cannot be disabled, you don’t have to use it…

See >>> Turn Private Browsing on or off on your iPad - Apple Support

To access Private Browsing in iPadOS15/16, it is necessary to first summon the Safari Sidebar using the button at upper left of the screen [1] - and from the menu tap the Private toggle button [2].

To return to regular browsing, tap the sidebar n Tabs button (highlighted here in blue), that appears above the Private button. Until re-enabled, Safari will remain in its normal browsing mode.