I know it's a little weird, but we have removed bearer-only clients from the new admin console. If you have a bearer-only client created with the old admin console, it will still show up in the new console, but you will not be able to change its access type.
To create the equivalent of a bearer-only client in the new admin console, just uncheck all the Authentication flows.
You can learn more about the rationale for this here:
https://groups.google.com/g/keycloak-dev/c/dvgDVYn1P2E/m/VjkFF2DUAQAJ?pli=1