How to do a realistic render of an environment/model?

I see on movies like Disney's live action The Jungle Book they were able to render an incredibly detailed and realistic looking environment. If I didn't know any better I would of thought they shot the movie in an actual Jungle (besides the talking animals of course). How exactly do they accomplish such realistic renders? I know they probably use there own proprietary software in most cases, but for the average Joe, what software and techniques can I use to try and render some screenshots with that sort of realism?