I think you want guided access: https://support.apple.com/en-us/111795 https://support.apple.com/en-us/111795 Or screen time, taking advantage of the content re

I think you want guided access: https://support.apple.com/en-us/111795 https://support.apple.com/en-us/111795 Or screen time, taking advantage of the content restrictions settings that let you disable most everything, including app install.