1) Go to the redeem page: -
https://www.reallusion.com/voucher/default.html?type=300
Process wise, it is similar to redeeming a Content Voucher: -
https://kb.reallusion.com/Purchase/50323/How-do-I-redeem-a-Content-Voucher
2) Once redeemed, go to your Member account - Order page to check.
In the Order page, the "Download" will link you to the Cloud Animator subscription page: -
https://www.reallusion.com/cloudanimator/subscription.html