Is this CGI? & would it make a good Blender project?

Yeah, and they do also on set/on location. On set you can control the lighting on the fake backdrop easily. On location you might block with ND and/or balance out the lighting with additional interior lights. But in this case they obviously wanted things to look more realistic.

Here is what I would use for cheating, and as you can see, you can take it waaay too far (for illustration, I wouldn’t really do this :D).