Symantec Endpoint Protection 12.1 (Enterprise) and Symantec Endpoint Protection.cloud are 2 different products.
In Symantec Endpoint Protection 12.1 (Enterprise), you have a Symantec Endpoint Protection Manager installed physically on server whereas in Symantec Endpoint Protection.cloud you have a different Manager.
You cannot import any settings Symantec Endpoint Protection Manager 12.1 (Enterprise) to Symantec Endpoint Protection.cloud Support Manager.
In your case, you would have to uninstall SEPM and SEP clients (Enterprise) and then get the .cloud installed.
Symantec Endpoint Protection.cloud
Secondly, check this Thread with similar query -
Hope that helps!!