First thing first. 

 Generate CSR from below link

     https://csrgenerator.com/

Save the key and Private key securely.

A Certificate Signing Request (CSR) is a formatted message that an applicant for a Secure Sockets Layer (SSL) digital certificate sends to a certificate authority (CA)The CSR contains information that the CA uses to create the certificate, including the organization, country, and common name.

 

Get a free certificate 

https://www.hostingwalay.pk/ssl-certificates.php

 

Certificate (CRT) will copied to CRT

PRIVATE KEY WILL go Pem keys