From the video....
View attachment 18501
So... you take the 2230, Win 11 SSD out of the left slot, and put it in the right slot.
Then, you can put a 2280 SSD in the left slot.
This is the one they used in the video...
Crucial P2 1 TB M.2-2280 PCIe 3.0 X4 NVME Solid State Drive (CT1000P2SSD8)
pcpartpicker.com
This is shown in the video, starting at 4:35
OR... you can just buy one of these (overly expensive), and stick it in the right slot...
Increase the storage capacity of your Dell™ System with 1TB Solid State Drive from Dell. It boasts a storage capacity of up to 1TB, enabling users to store large amounts of data.
www.dell.com
Could only find 1TB 2230 SSD (M key), at DELL or Ebay.