It’s been a while since I opened that project, but yes everything you see in the video is contained within the project.
You want to download the “A Boy and His Kite” from the Learn Tab -> Engine Samples section. is the complete demo with landscape, deer, the boy, and kite’s. 
Be warned that is a very performance heavy project if you stream in all of the levels at once (takes around 20gb of ram to load it all in), so if your PC isn’t so great, don’t enable the other levels in the viewport. I get around 50fps with an i5 4670k, GTX 980, 24gb ram.
The “Open World Demo Collection” only contains some of the assets used, it’s a smaller download sample pack basically.