Set child template

Is there a way to for example to tell that all children templates from a pages are a kind of template only?

Italo.

Not sure I understand your question. Do you mean to limit selecting a template on page create to a single template?

In a pages section, you can set the create option (or simply the templates option). If only a single template is set, then all children are created with this template. If the templates option contains multiple options, use create to limit which template can be used when a new subpage is created.

sections:
  pages:
    type: pages
    template: mytemplate

Or

sections:
  pages:
    type: pages
    templates: 
      - template_a
      - template_b
      - template_c
    create: template_a

Is correct. That exaclty what i was looking for,.