This is probably common knowledge for most people here but thought it could be useful
Apply for a license from HAK5 C2
Get a Public IP such as (18.104.22.168) for your server
Get a public domain and point the dns record such as "cave.domain.com" to the IP 22.214.171.124
Allow the DNS propagation to take plus I usually wait around 24 hours as Let's Encrypt DNS seems to be delayed a bit
Ensure your servers firewall inbound rules allow "http (80) and https (443)"