You can translate content added to a Site Studio Template via the interface translation module.

Enable the Interface Translation module¶

Enable Drupal 8 core "Interface Translation" module. You can do this by going to "Extend" and then searching for "Interface Translation" and enabling the module. 

Translate your content¶

1. Navigate to Configuration > Regional and Language > User interface translation
2. Search for your content in the filter
3. Enter a translation for other languages 
4. Click Save translations.