Access from remote in HA and WebMin configuation

[Danieleeffe1]

I want to access my HA installation from outside.

looking in the guide I read that it is possible with a VPN

I have an ubuntu server and I want to install OpenVPN to use it to access my HA installation remotely.

To do this I need to install EasyRSA
to install EasyRSA I need webmin (I know how to use it and I'm happy with it)

I created a user dedicated to webmin in HA

SETTINGS>PEOPLE>USERS>+USERS (button)

once the user was created I went to:
SETTINGS>DEVICES AND SERVICES>+ADD INTEGRATION

I searched for webmin and a pop-up opens which I fill in but it always gives me an error:

what is the host name to use?

I tried with:
homeassistant.local
homeassistant
localhost
ip address (xxx.xxx.xxx.xxx)
I tried to configure a static IP in my internal network from HA and Router
I tried changing the hostname to HA...

I searched the forums but I can't find a specific and clear guide.

Thanks for any help you can.