You ll need a hard drive and an enclosure to add your own storage to the xbox one a good choice would be the orico toolfree for 3 5 or ssds to serve as the enclosure it can use multiple.
Adding usb storage to xbox one.
Once automatically detected follow the on screen prompts permitting.
A message will pop up on screen to show it recognises that.
Plug an external hard drive into your xbox one via a usb cable and assuming the drive is fast enough the xbox one will be able to install games to that drive.
External usb hard drives can now be used as storage space on the xbox one to configure an external usb hard drive for use on the xbox one the usb drive must be usb 3 0 and have at least 256gb of space.
Plug it into one of the three usb 3 0 ports two on the rear one on the front or side depending on the model when the xbox one is on.
With a drive in hand it s now time to connect it to xbox one.
If the external drive meets the requirements the following will appear on screen the first time the drive is connected to the xbox one.
Currently there is no external storage options on the xbox one and to be honest i doubt that they ll support nas for things like games etc.
Adding an external hard drive the easy microsoft approved way to expand your xbox one s hard drive space is to add an external hard drive.
To get more storage space consider getting an external hard drive for your xbox one.
Microsoft s only caveats for what the xbox one will support is that it has to be at least 256gb in size and be usb 3 0 compatible.
The only way you can play media from a nas at the moment as theninjajedi has suggested is to find a way to use playto to send it to the xbox as this is supported.
This means you ll be able to keep everything you have.
Connect the drive to a vacant usb port using the included cable.