Note: below process subject to having relevant roles and permissions.
Over 2020 we introduced a new interface, and new Staff and Student Details pages.
Administrators can set whether users are able to switch between the old and the new user pages and interface from Configuration. For example, you might wish to force all users onto the new interface.
To do this, navigate to Config > Setup > System > New UI Settings and you will see the option to change what your users can do.
Users will then have the option to switch between interfaces: