By the way, in Chrome you may click the pad lock icon at the address bar to know about a website's SSL connection details.
In this example we will generate a private key named sudo2016.key and CSR file named sudo2016.csr. For your purpose, rename the file names with the names you desire.
Generate an RSA Key
openssl genrsa -out sudo2016.key 4096
Generate CSR
openssl req -out sudo2016.csr -key sudo2016.key -new -sha256
Pre-SSL Certificate Generation
The contents of the CSR will be supplied to the SSL provider. The SSL Provider will generate a number of certificates for you.
In Name.com, they provide three certificates: Server Certificate, CA Certificate and the Root Certificate.
Different Web Servers have different ways of installing SSL certificates. Usually, the SSL Providers give instruction for every Web Servers.