You ll need two drives.
Can you partition an external hard drive for xbox one.
Then choose a partition style and confirm.
Here highlight system and select the option labelled storage.
You need to initialize the hard drive first and then recreate.
Select your external drive and press the a button.
Xbox one can only work with a maximum of 2 external hard drives at once.
I d recommend getting a 2 3tb drive for the xbox so it will do you for a few years.
But when an xbox one external hard drive is connected no partition is displayed.
Select the xbox one external hard drive which shows as disk unknown not initialized and choose initialize disk from the context menu.
Its a better idea anyway because if one fails you ll only lose have the data.
There should be proper partitions on the drive.
The usb storage should have a 3 0 connection type.
In order to store games it should have a capacity of 256 gb or more.
In the pop up menu that appears select transfer.