Unable to add repos to subscription manager for the online labs

[Sanjay2019]

I have a Redhat Learning Subscription and I am trying to do course DO180R.  I am login in to the GNOME based workstation. I am opening a terminal to add the repositories to subscription-manager. And I am getting the following error:

subscription-manager repos --enable=rhel-7-server-rpms

Network error, unable to connect to server. Please see /var/log/rhsm/rhsm.log for further information. 

I checked the rhsm.log file and I see there's a connection refused error.

Any help will be greatly appreciated.

[Sanjay2019]

Looks like the workstation does not have any internet access. Without CDK being installed in the workstation, how should I do the lab lessons?