Extending and adjusting core strapi

System Information
  • Strapi Version: 4.2.0
  • Database: PostgreSQL

Is there a way to extend Strapi’s core feature and adjust them for my personal usage. For example I want to add the localization feature for the existed roles so I can give rules to my employees depending on their region so they can access the entries with specific locale and not all the entries.

I believe that comes with the premium version.