Wordpress Cloudflare plugins unable to integrate with Cloudflare

Currently, We are using CNAME with static website in cloudflare.
Now My wordpress website ready and want integrate with Cloudflare. Now domain is already registered with cloudflare so no need to setup new domain.
We need global API key and email to sign in Wordpress but when I signed In Cloudflare plugins. I am getting error “It looks like your domain wpcomstaging is not provisioned with Cloudflare.” and it not showing other confiuration/setup option.

I am unable to understand setup. Should I remove all existing DNS record from cloudflare then only possible integration with wordpress. If I remove existing DNS record then it would down our website.

Error Message