You can easily create your own Origin certificate within your Cloudflare control panel.
Log in to your Cloudflare control panel:
1. Select the domain name you would like to generate the certificate for, then select Crypto (the padlock icon) from the menu at the top of the screen
2. On the right-hand side, select Create Certificate
3. Complete the relevant fields to create your 15-year certificate. Select Next
Now that you have your private key and certificate, please contact us to install it on the server.