Why does my site doesn't have SSL Certificates?

I’m not going to visit a website I don’t know, and why would it help me help you? You could go to ssllabs.com and run their server test from there. It might tell you something useful. The man who makes that site wrote OpenSSL Cookbook. Get a copy or look at the online copy. Also note that Certificate Authority (CA) Let’s Encrypt has nice documentation, including a nice glossary webpage to explain terminology. Let’s Encrypt issues SSL/TSL certificates via an API on their ACME server that requires a client program.

You need to get a certificate from a CA. Browsers follow the chain of certificates and keys, starting with your Web server’s, until they get to a root certificate they trust. The root certificate is created by a trusted CA and know to the browser. It has a store of trusted root certificates. You have some studying to do. I expect weeks, but maybe just days if you are brilliant, I don’t know. Get your website to work at something with http before you try to add https. Break up deployment into increments so you can isolate one problem at a time and know what went wrong. Three problems at once is very difficult to solve. Hello world is the way to start, just some static page with http. The SSL problem does not matter if you are using http (and port 80 by default). Eliminate other concerns that must work before SSL/TLS matters. Learn about the theory of certification. The OpenSSL Cookbook is pretty much mandatory. Some general overview stuff is online. Might want to look at that before the Cookbook.