Using Cloudflare with Wix
You can use Cloudflare with Wix websites, though your setup needs to be different than with most website builders.
This is because Wix does not support using Cloudflare nameservers (which is the normal part of a full setup or with domains bought through Cloudflare Registrar).
Using domain pointing
If you want to manage your DNS through Cloudflare or you bought a domain through Cloudflare Registrar, you can connect that domain to Wix through domain pointing.
This method means your website is using Cloudflare for DNS only, so all your DNS records should be DNS-only (unproxied).