Immich with external NAS

Hello everyone!
I’m new to this channel and would like to start using Immich for a local backup of my pictures.

I’ve installed Umbrel OS (https://umbrel.com/) and the Immich application. However, I want to use a NAS in my network for storage. Unfortunately, Immich only reads hard drives connected directly via USB, and the USB hard drive I currently have is already in use for other purposes.

The NAS I want to use is a Western Digital 4TB (RAID1):

I can create a shared folder with account credentials on this NAS for Immich to use as storage for my pictures.

Is this possible?
Is there a way to achieve my goal?

I tried to find a way with only hands but probably I missing something.
On GITHUB I found this:

It seems that it possibile but I can not it work in my network.

I can provide any information need to help me on this.