So you installe HassOS… You installed the add-on “DuckDns with Let’s encrypt” with something like this as parameters:
Than you open the port on your router by mapping for example external port 15000 to port 443 of your internal IP address where HA is installed
You access HA using : https://your_dns:15000
Your DNS (your_dns) should of course be the same than the one you used in the parameters of DuckDNS
To access HA internally without https (http://HA_nodename:8123), you have to install NGINX with the parameters like this (it is just an example):
