It is important to clarify that "full screen" typically refers to the standard 4:3 aspect ratio, which was the dominant format for television screens in the past. However, most modern televisions and streaming services use the wider 16:9 aspect ratio, also known as "widescreen."
While "Harry Potter and the Deathly Hallows – Part 2" was filmed and released in the widescreen 16:9 aspect ratio, it is possible to find copies of the film that have been cropped to fit a 4:3 aspect ratio, which would be considered "full screen" in the traditional sense.
So, while "full screen" is not the standard format for the film, it does exist. You might encounter cropped versions on older televisions or streaming services. However, most viewers will watch the film in the original widescreen format.