Here are the instructions for enabling the Scout Cat. Enabling Julius Caesar will work the same way.
New 2K Account
Signing up for a 2K Account is easy! Simply go to
https://accounts.2k.com/signup and register. Once you’ve completed the sign up, link your Steam account and boot up Civilization VI. Once in the game, log into your 2K Account.
You can also create an account in-game. Boot up Civilization VI and navigate to the 2K Account button in the bottom right-hand corner. Click it, then follow the instructions to register a new account.
Existing 2K Account
If you’ve already registered a 2K Account, first allow us to thank you for your support. Unlocking the Scout Cat is a cinch – all you have to do is boot up Civilization VI, click on the 2K Account button in the bottom right-hand corner, then log into your 2K Account. Once your account is linked, you’ll have access to the Scout Cat.
Enabling the Scout Cat Unit
Once you’ve linked your 2K Account to Civilization VI, you’ll need to enable the Scout Cat skin. Restart Civilization VI and click the Additional Content tab. On the left side, you’ll see a list of all your additional content. Scroll down to “DLC: Scout Cat” and click it, then click on the “Enable” button.