If you really need to expose something to the internet set yourself up an SSO/OIDC provider and have it sit in front of the service and have a deny-first policy in place, whitelist the known few IP’s that need to connect regularly or alternatively geoblock.
Also suggest setting up some security headers, however headers can be confusing for beginners.

What distro are you using? There are 3 big distro’s you need to keep in mind for, Debian, Arch and Fedora, every other distro typically bases themselves off of one of these big distro’s.
Documentation is your friend, if you’re using a Debian based distros the
stress ngrepository linked above has this in their documentation -(run the commands below to install the package)
Now that is installed, they have an examples section.