Satellite 6.12 and above versions can be installed on RHEL 8 only. Here it is mentioned that 'Choose from the available list which operating system and version you are installing on' but the statement is not valid as the suggested steps are applicable for RHEL 8 only. Following statement can be removed:

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Choose from the available list which operating system and version you are installing on:

[Hyperlink]Red Hat Enterprise Linux 8
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Reported by: rhn-support-mkalyat

https://dxp-docp-prod.apps.ext-waf.spoke.prod.us-west-2.aws.paas.redhat.com/documentation/en-us/red_hat_satellite/6.13/html/installing_satellite_server_in_a_connected_network_environment/installing_server_connected_satellite#annotations:4c7ec890-647b-4281-8171-72b2682907fe