All of our themes come with a default collection template and a set of predefined collection templates that you can use to get started. This default template is what resources use if you don't have an alternate template explicitly set.
Any changes you make to a template will impact all collections that use that template. If you want to display some pages of a particular template differently, then you can create a new template based on one that already exists in your theme.
Create a new collection template
In the theme editor, click on the page selector at the top of the page, then click on Collections, and then click Create template.
In the Create a template modal, enter a name for the new template in the Name field. Under Based on, select the template you want to base your new template on, then click Create template.