If you did an install with the demo content it’s there under templates, named MODx Host.
If you didn’t install the demo content then run the installer in upgrade mode and install it.
So I tried to do the upgrade mode and did not see any option to select the "Modx Host" template.
Now, I can’t log into my manager. I enter my username and password, and it loads the same page. It does not tell me its the wrong password, it just reloads the same page. Some sort of session problem?
The templates are installed automatically with the demo content.
Once your inside the Manager you should be able to edit them.
I’m not sure why you can’t login, I’ve never had that issue.