It seems that I cannot Get started
to set up a Kiosk account in Windows 11.
Why do I not see the option to set it up?
The kiosk feature is not supported in the Windows 10/11 Home editions.
Sorry for the negative answer, but you will need to upgrade your version of Windows 11 in order to have this mode.
Reference : Configure kiosks and digital signs on Windows desktop editions
Which edition of Windows client will the kiosk run?
All of the configuration methods work for Windows client Enterprise and Education; some of the methods work for Windows Pro. Kiosk mode isn't available on Windows Home.