Ubuntu Core installation is different from other methods of installing Ubuntu.
That is not a setup or profile screen. Your install is already complete. Your user has already been created. The newly-installed system has already booted and is running. That screen merely tells your new system's ssh login name and IP address(es).
The next step is to use that login name and IP address: SSH into your new, fully-installed Ubuntu Core system (from a different system that has your SSH key) and begin customizing it.
SSH is a required step. First login cannot be done locally as your account has an SSH key but no password. During that first login, you can optionally set a password for future local access.
You mentioned in a comment that you do not have an SSH key uploaded to Ubuntu One. Without that SSH key, your newly-created user cannot login to Ubuntu Core at all. There is no known workaround or bypass for this requirement. It's a key element of the Ubuntu Core design.
Folks who don't want to use SSH or don't want to upload a key might perhaps consider a different flavor of Ubuntu that better meets their needs.
You mentioned in a comment that you added an SSH key to Ubuntu One SSO later, after the install was complete. Unfortunately, the SSH key must be in place on Ubuntu One SSO during the install process. There is currently no boot command to make Ubuntu Core refresh keys.
Now that you have a key uploaded to Ubuntu One SSO, reinstall the Ubuntu Core system to create a user with a working SSH key.
