Adding an SSL certificate is really important for modern web applications or websites.
So without taking too much time, let's dive directly into the free SSL implementations site.
First login to ZeroSSL website to generate SSL certificate.
After sign up, you just click on the New Certificate button to generate a new SSL certificate for your website.
Then, add your domain name, and move to the next step.
You have three options to verify your domain, choose any one of the options.
After verification, you will have the certificate to install in your website server.
For further details, you can go to their official documentation.