I'm not affiliated with either, but I use rathole (https://github.com/rapiz1/rathole) and kamatera (https://www.kamatera.com/) as my own kind of ngrok. But I've also heard good things about tailscale (https://tailscale.com/pricing/) which has a free hobby tier. Gonna give that a try after work today.

WireGuard in Docker - then open a firewall port.

However to get it actually simple, Tailscale. It’s truely ludicrous. I had it running inside 10 mins, but only because I wasted 5 minutes trying to work out what to do next, when it was already running.

I use ZeroTier, which you can host yourself or use a hosted service. I haven't tried tailscale, though, which is what a lot of others seem to be using here.

I started using netmaker recently And it is running great on all of my devices so far.

Tailscale