A CSR also known as Certificate Signing Request file which is generated on the physical web server that validates the server-specific information about the server and the organization which owns the applicable domain.
Typically, the following Organizational information is required in order to generate the CSR via the physical web server.
State or province
City or locality
If you wish to secure “www.mydomain.ca”, then you will need to enter the exact host “www” and domain name in this field. If you enter “mydomain.ca” then the Certificate issued to you will only work for the domain name “mydomain.ca”. It will cause an error when someone accesses the domain name as “www.mydomain.ca”.
CSR keys are typically obtained by contacting hosting provider for the respective website. If access to the physical web server or web-based control panel is possible, a CSR key can likely be generated directly without assistance.