Nobody else mentioned DuckDNS. It’s free and has worked great for me for years.

You’ll need to install a client that syncs/auto-updates your public IP, then pretty much never touch it again.

Ah, sorry I hadn’t appreciated you were after split tunnelling… You can do this with Tailscale for services where you’re connecting to a fixed IP/FQDN, which I think rules out torrenting/P2P unfortunately.

The only way I’ve seen to pass a specific app’s traffic through Tailscale appears to be an Android exclusive feature.

If I’m wrong someone please correct me!

You can absolutely use Tailscale; your host in the unrestricted country needs to be set up as an exit node (CLI argument in Linux, or a menu option in the system tray in Windows.)

Then, your local machine needs to be set up to use that remote machine as its exit node. (tailscale up --exit-node=remote-tailnet-ip-here)