Workspace templates
Share a site as a starting point for new sites in its workspace.
Workspace template… in the site menu shares the site as a template of its workspace. Turn on Save as workspace template: everyone in the workspace can then start a new site from it.
Start a site from one
Templates, in the top bar, lists your workspaces' templates. Choose one and Use this template, give the Site name, and choose whether to Copy its collections and items. Create the site makes it in the same workspace and opens it in the editor.
The new site is a copy of the template as it is then: its pages, styles and languages, its images on the same files. Changes to either don't reach the other. Owners, admins and designers of a workspace can create sites in it, as long as its plan has room for another site.