If you don't understand these terms, you probably shouldn't be exposing any kind of port on your router. Seriously, not being snarky.
I used to teach multiple levels of Cisco classes, and I wouldn't expose a port these days, I don't know enough.
Instead, I'd recommend using Tailscale on a home machine and your mobile devices.
Using Tailscale, you can also selectively expose a service to the wider world (not just devices running Tailscale), using the Funnel feature.
I'd say it's your safest intro to accessing self-hosted resources from just about anywhere.
Edit: a couple years ago I opened a port helping a friend test something, I forget what. Within hours I was getting hammered with thousands of requests per hour, people trying to break in.
I wasn't worried because of the security we had, but it was annoying, and potentially a massive risk.