Using a Template
Once the template has been created, you can create new sites from it, in couple of different ways.
From the Sites screen
Click on "Add Site" button and switch to "From Templates" tab.
Here, you will find a list of templates created by you or your team, select a template you want to create a new site as a base.
What is a template, exactly?
A template consitutes of two things - backup of all files and database export of a site.
From the Templates screen
In this list of templates, click on the "+" button on the template row you are interested to create a new site from.
It will then ask you a name of the site, and proceeds to create a new site.
Templates + Git integration
If you are looking for Git integration with templates, then navigate to the Deployments section to understand the link between the two.