Hi @Malakay
Welcome to using Freedombox.
I’ll try my best to go over your questions. I won’t be able to answer all of them but maybe give you a few pointers on the way.
Freedombox (FBX) is a Debian Pureblend. That means it’s Debian at it’s core (not a distro).
With FBX you can do anything you could that’s possible with Debian, as long as you know your way around.
FBX serves to help you self-host. It’s specifically designed to be hosting so converting it to work only for your intranet will need some adjustments. Have a look at this post.
FBX can act as your router if you use it in DMZ mode (bypassing your modem’s functions and transforming it into a mere “bridge”). All the options presented to you on the initial setup will be necessary for i.e. your port forwarding, firewall settings, as you install apps.
can you give more detial on this? i.e. you setup static ip address on your router? or you have a static ip address on you wan? which device did you restart? a little information on your exisitng network/device configuration would help.
Once you install it, Radicale will restart by itself after every reboot of your FBX.
PiHole is not an application in the Debian repos. So, untill it’s maintained in Debian and configured for FBX, you need to download, install and run it manually. It is technically possible to run PiHole on FBX just as it is technically possible to run it on Debian.
There are varios VPN clients that you can install from the Debian repo (OpenVPN being one of them). If you know your way around to configure these clients manually, then sure, you can run it off FBX. Nevertheless, FBX comes with OpenVPN fot the purpose of connectiong to your home server from WAN (the otherway around of what you’re looking for).
Hope these help.
Good luck and hope you have a good experience with FBX.