Am I right that we cannot create a single page using the API?
From what I can tell you can only create a subpage? https://getkirby.com/docs/reference/api/pages/children-create
Should be possible via the site endpoint? https://getkirby.com/docs/reference/api/site/children-create (for a page on the top level). For subpages, the endpoint @waffl posted would be the right one.
Thanks for answering… The site endpoint works but I was confused why this isn’t possible with the page endpoint. Not as obvoius as is could be 
Are there technical restrictions on kirby side? Or why does this method not exists?
I don’t know, but since pages are either children of the site object or of another parent, this maybe didn’t make sense?