What are you using as a Google photos alternative? Currently I’m using Nextcloud but I’m thinking of switching to a more dedicated solution.
I mainly need to upload photos from my device automatically, have an UI to see and classify them, albuns and sharing.
“IP” in this context means “internet protocol address”. A public IP is one that can be accessed from outside your home (what you see when you go to https://whatismyipaddress.com/). A non-public, or internal, IP is the one your router gives your computer, frequently starting with 192.168. This can be accessed by other computers on your network but not from outside your network.