Would the plan be the Advanced Certificate Manager
Advanced Certificate Manager allows for more control and flexibility for your certificates and SSL/TLS settings.
Cloudflare doesn’t allow downloading of any trusted certificates.
You can install the self-signed Cloudflare Origin Certificates, which are issued, and trusted, by Cloudflare itself for you origin server, when put behind the Cloudflare proxy. Do note that these will not be trusted by your browser directly, so you need to pass through Cloudflare’s proxy for all uses.