Yes that would explain it then, you need to upgrade to Kentico Xperience 13 to gain this bit of functionality.
By upgrading to Kentico Xperience 13, you'd also gain other features from the latest refreshes, and also opens up the possibility of using .NET Core rather than .NET Framework for your presentation website.
To replace your license key in Kentico 12, you need to open up the Licenses application in the admin interface and add your new license in there.