When user groups are first created, we do not create full training accounts.
If you would like to convert a user into a training platform account, just click the "Create Training Users" button from the Users & Groups list.
Then select the users (or all) you wish to have access to training platform and click "Create User(s)".
This will then create the Training account and send an email to the user with details on how they can set their password. These users can then be selected when creating a training campaign.