Step 1: Login into your server using RDP using Administrator login details.

Step 2: Open Information Services (IIS) Manager
To open IIS Manager :-
On the Start menu, click Administrative Tools, and then click Internet Information Services (IIS) Manager.

Step 3: Select the required server and open the “Server Certificates” option.

Step 4: On the right hand side options, click on the “Create Certificate Request” button.

Step 5: Enter all the required information for the CSR and then click on Next.

Step 6: Choose a bit length of 2048 and go to Step 7.

Step 7: Choose the location where you want to save your CSR and click “Finish.”

A CSR TXT file has been generated.
Step 8: Download the certificate from the SSL panel.
Step 9: After receiving the certificate, submit the SSL certificate.
completion of the certificate.
9.1: Open the IIS and Server Manager and click on the Complete Certificate Request.

9.2: Add the certificate and fill in all the details, then click on “OK” to complete the request.

9.3: The Certificate has been completely submitted.
Step 12: Bind the certificate and add domains.
10.1: Open bindings options in default web sites as shown in the below screenshot.

10.2: After opening the bindings , click on “add” to add the domains for the SSL.

10.3: Choose Type, IP, port and SSL certificate and then click on OK.

SSL has been successfully installed on the domain, please verify through the URL.
Thank you.