Is it possible to setup a remote smb or sftp login from a Mac to another Mac?

I'm struggling to find answers. I can find plenty of ways to connect locally (on the same network) to a Mac with file sharing turned on, but I can't find much information on remote connections (not on the same network).

Finder > Go > Connect to server: I can type smb://192.168.1.1 and I can connect to the Mac, but I can't find any way to use a public IP address. I assume this only works locally and not remotely.

Terminal: This article shows connecting via SFTP but again I can only get local IP addresses to work, not public IP addresses.

Allow a remote computer to access your Mac - Apple Support

I got SSH working 10 years ago, but I can't seem to figure it out now. Seems like everything only works locally and there's not much documentation on actual remote login options.