A Certificate Signing Request or CSR for short is a format for requesting a certificate. In addition to the public key, a CSR contains further information about the desired certificate. This includes above all a CommonName (the domain name) and the name and address of the applicant. The procedure is standardised.
A CSR is always generated on the server where the certificate is to be used. Data is requested that is also contained in the certificate.
For servers managed by MOORnetworks, you will find an SSL wizard in the respective administration console, which will generate the required CSR for you with a mouse click. For your own servers, follow the instructions of your server administrator.