The Audience Targeting app allows you to segment your audience, target specific content to different user segments, and create campaigns to target content to user segments. It was deprecated as of Liferay Digital Experience Platform (DXP) 7.2 and will not be released.
Many of the features and functionalities present in the Audience Targeting app are now included out-of-the-box with DXP 7.2 as part of the Segmentation and Personalization component.
Migrating from Audience Targeting will involve some manual steps and has been documented in the article Manually Migrating from Audience Targeting. After reviewing the documentation, if you need further assistance please open a support ticket.