Certificate Signing Request

I need information to create SSL via register.com which has my thailandupc.org domain and they need you to provide me with information called "Certificate Signing Request".  Here is what register.com says:

"

SSL Certificates Submit Certificate Validation Information

Provide CSR
A Certificate Signing Request (CSR) is a body of text containing encoded information specific to your domain name or organization. You can get your CSR from your Web hosting provider and then paste it into the box below. If you do not know your Web host server software, please contact your hosting provider, or select 'other' from the drop-down list.

We will decode your CSR information and you will be given the opportunity to confirm and/or update your information before submitting for validation.

Please note: The minimum key size for all SSL Certificates is 2048 bits."