Here is an easy way to add a new https site with a Let's Encrypt certificate using Nginx and acme.sh.
Configure Nginx
# File: /etc/nginx/sites-available/default server { listen 80 default_server; listen [::]:80 default_server; server_name _; location /.well-known { # <- here is the trick root /var/www/html; } ... }
~/.acme.sh/acme.sh --issue -w /var/www/html -d example.org