Currently Wix Website Builder doesn't support Cloudflare.
If this is a feature you would like to see made available, please contact Wix or vote here (this link will take you to the Wix website).
Here is a list of other website builders that do support the Cloudflare service:
- Shopify (using Cloudflare with Shopify)
- Squarespace (using Cloudflare with Squarespace)