Where do you download the apocalypse DLC for black ops two with a season pass?

To download the Apocalypse DLC for Call of Duty: Black Ops II with a Season Pass, you should access the digital storefront of the platform you are using, such as the PlayStation Store, Xbox Live Marketplace, or Steam. Once there, navigate to your library or the section for downloadable content (DLC) to find the Apocalypse pack included with your Season Pass. Simply select it and follow the prompts to download and install the content.