

Same as the other reply here, if you’re on your local network most likely be a 192. address. You can find this on the host server by the “ip a” command.
Personally immich is pretty advanced for someone new to homelab, you might find starting with homeassistant or something might be easier to get started. Also immich is super beta right now and prone to drastic breaking changes with each update.
On the NTFS thing, Steam really does not like NTFS drives in my experience. Converting to Ext4 would be a good idea for gaming purposes.