Sorry about this.
Installed Buster, Snap and Nextcloud from snap. It works fine so far. Thought Pico CMS would be good. Yes I can use my settings to create a working example site that is accessible as part of my domain.
How can I edit the files that make up the site? I cannot find them on the server, but they must exist (obviously).
they are stored in the appdata directory of you data folder. Log in as admin user to your Nextcloud. The instructions incl. the exact path can then be found in “Settings” -> “Administration” -> “Pico CMS”.
In a snap installation, I guess the files can be found somwhere in: /var/snap/nextcloud/common/
https://github.com/nextcloud/nextcloud-snap#where-is-my-stuff
Thanks bb7. I did find it and the Settings>Admin>Pico route will doubtless be the best way to sort other things out.