iMac 24" problem with using Current User

I have just purchased a new iMac 24" 2021 and am trying to upgrade to macOS Venture 13.0.1. When I click the Upgrade Now button I and asked to supply my admin password which it did and I and told it is not recognized. When. I go to User and Groups area I am show as Admin with allow user to reset password using Apple ID highlighted and checked, but Allow user to administer this computer is checked but grayed out. I can unlock the Users & Group.

If I selected and old name from my older computer which shows up in Other Users section and listed as Standard the Allowed user to reset password using Apple ID and Allow user to administer this computer are available but not checked.

I have used my Current User name (which is different from my old iMac's user name) and the password it set up for it for any other task that requires a password connected to the current user name.

Help