Hi kath_vallei,
I assume you have GenieACS up and running, properly configured to the authentication method you want to use. If this is not the case you might want to take a look at Physical lab experiments with GenieACS where I introduced my docker based setup for lab experiments. The term ‘device under test’ i.e. DUT can be read as CPE.
Then simply store the URL pointing to GenieACS into your device, together with the needed credentials like certificates and/or usernames/passwords. This depends on your CPE.
Best regards,
Chris