Elementor templates are global designs, which can be used in many posts/pages, and edited from one place.
Accessing templates from Theme Builder
Editing the template directly from the frontend
When you are on specific page, and wonder if the page uses templates, and what templates are used, just hover over the Edit with Elementor button.
It will drop the list of used templates and their types.
Here are few examples:
You can also see on the screenshots, that from the dropdown list, you can access Theme Builder, and Site Settings.