“Use our fast SSL Checker to help you quickly diagnose problems with your SSL certificate installation. You can verify the SSL certificate on your web server to make sure it is correctly installed, valid, trusted and doesn’t give any errors to any of your users. To use the SSL Checker, simply enter your server’s public hostname (internal hostnames aren’t supported) in the box below and click the Check SSL button. If you need an SSL certificate, check out the SSL Wizard.”
Various types of SSL Certificates can be purchased from SSL Shopper
More Information About the SSL Checker
Generating a CSR is only used for paid SSL certificates that include information such as country, organisation and so on. The paid certificates are issued for 365 days.
The free SSL Let’s Encrypt doesn’t use CSR and is being issued for only 90 days. This is what Let’s Encrypt offer and cannot be changed. The free SSL automatically renews each 90 days and no actions are required.
If you would like to have a SSL for 365 days you would need to purchase one. Then you would need a CSR.
You can check your SSL certificate status here – https://www.sslshopper.com/ssl-checker.html
In order to issue a free SSL and install it on the server you would need to add the domain first. The SSL are installed on the server, where the domain resolves from, not on the actual domain name.