The purpose of the “change enablement” practice is to maximize the number of successful service and product changes by ensuring that risks have been properly assessed, authorizing changes to proceed, and managing the change schedule.

The purpose of the “release management” practice is to make new and changed services and features available for use

The purpose of the “deployment management” practice is to move new or changed hardware, software, documentation, processes, or any other component to live environments. It may also be involved in deployment components to other environments for testing or staging.

Study case :
You need to update your mobile application, 1st of all you need to assess the impact and** risk ** of this update , authorizing the change by the change authority , and adding the change to the change schedule after assigning the needed resources <<These are change enablement activities>>
in the night of the change , you need to apply or compile the new code or the new features to your existing code (either on test or on live environment) <<These are deployment management activities>>
once you make the new feature available for the user - Update available in Google play or Apple Store for download and being ready for use <<These are the release management activities>>