The Photos module allows you to create content manually, or bring in an existing RSS-based photo feeds, such as Instagram.
To manually add news content, go to Add Content -> Photos -> Manual. This will automatically create a new collection which you can additionally modify to your needs.
To add an item to that collection, click on "+add item" and fill in the content.
That way you can add as many collections and items as you want.
RSS addingTo add an RSS feed, go to Add Content -> Photos -> RSS/Instagram and paste the RSS feed link.
To add an Instagram feed, you can follow this tutorial: https://support.shoutem.com/article/302-instagram-integration
Once your galleries are configured, placing them into your app will result in a similar interface to the one below: