Drupal Multisite

Drupal Multisite is a feature that allows you to manage multiple websites from a single Drupal installation. This is especially useful for advertising companies that need to manage websites for different clients or campaigns. With Drupal Multisite, you can create separate websites with unique content, themes, and configurations, while still benefiting from the centralized management and security of a single Drupal instance. This makes it easier to scale your advertising operations and manage multiple websites efficiently.

Website: https://www.drupal.org/docs/core-modules-and-themes/multisite