This will require that you have followed the ProxDocs guide to install and use Nginx.
SSL will allow users to access your instance in a secure manner. Using Nginx and Certbot will allow you to generate and use SSL certificates for free. To install Certbot, run the following command:
$ sudo apt install certbot
After installing Certbot run the following command to add SSL to your site:
$ certbot --nginx -d your.domain.com
Don't forget to replace your.domain.com
with your actual domain.