To list all templates in a unit in postman, go to the ‘Templates’ page on a unit, and press the ‘code’ icon at the top-right of the page
Here you choose the API key you want to choose. In case you do not have an API key, you can follow this guide. Then go to the ‘Postman’ tab, and finally press the ‘Copy to Clipboard’ button at the bottom of the page.
Finally, to use the snippet, you need to import it to postman, the guide can be found here