While Site Studio utilizes the Drupal 8 core template suggestions (including page, content and field level templates), the terminology is slightly different.
Templates that would have the suggestion: page.html.twig are called "Master templates."
Templates that would have the suggestion: page--content-type.html.twig are the content view mode templates.
Field templates remain unchanged as fields are added to Site Studio templates using the twig field variables that Drupal supplies as default. For example:
Note that the layout canvas field renders out as a Drupal field. The content and styling for each layout canvas field on a content entity is stored against the field inside content (so there is a pure separation of content and templates).
There is a new class of templates for components. These are added dynamically inside any master template or content template as needed and can contain Drupal fields and other component fields.