After reading How to install an Origin CA certificate in NGINX this article i just add this few line of code after listen 443;,
code are :-
# ssl_certificate /var/www/ssl/certificatefree.pem; # ssl_certificate_key /var/www/ssl/freekey.key;
then trying to open the website and getting Error 521: Web server is down error.
CAn anyone help me here to fix my problem.