Here is how to get your Twitch Prime Benefit
If you have a Twitch/Amazon Prime membership then you can now claim your Call Of Duty: WWII benefits.
The first lot of content you will get is a Bomb Voyage Zombies Camo, your Supply Drops for this month. You also get 2 additional Winter Siege Supply Drops with one being a Premium Drop which gives you 3 Winter Siege items, and the other is a regular Winter Siege Drop which only gives you 1 Winter Siege item and two regular items.
To link your Twitch Prime account to your Call Of Duty account you will need to click on this LINK. If you are on PlayStation 4, Xbox One or PC you will be able to claim your loot.
Once you have linked your accounts you will need to follow these instructions to claim your loot,
Instructions to access your in-game loot:
1. Complete the Call of Duty: WWII in-game tutorial (if you haven’t already)
2. Visit the Mail Officer to receive the Bomb Voyage weapon camo and open your Supply Drops in your inbox.
3. Subsequent Supply Drops will be delivered to your inbox in the Mail Officer approximately once a month for this promotion, so long as you remain an active Twitch Prime member during the promotion period. Your game account (PS/Xbox/Steam) and your Activision account must remain linked to receive content.
There will be more content to come over the next six month as long as you keep active your Twitch/Amazon Prime membership.
Source: Twitch Prime