My goal is to SSH into my Pi on my LAN (local area network) from WAN. Basically, I want to SSH to a Pi that is at home and that is connected to the router from places like school or work.

I thought that I would try opening a port on my router so I went to my routers NAT settings and changed service to SSH (since thats what I want, right?).

I am later going to put Pi's local IP in the "Server IP Adress" bar. But I am somewhat uncertain whether it would be (somewhat) secure if I were to open a port like that. Like, is that all it takes? I am new to the networking scene and hence lack experience in this regard.