Faceless Documentary YouTube Videos

I've been watching a lot of faceless documentary style YouTube channels like Magnates Media and I'm wondering how do they use so many images and video clips they don't own without getting into copyright trouble?

Is this all fair use? How does that even work when you're using footage from companies, old news clips, stock images, etc.? Do they just risk it and rely on fair use?

Also, I’m from India...does the whole fair use thing apply the same way here, or is that just a U.S. law? I’m thinking of starting a similar YouTube channel and want to know how people go about sourcing visuals legally (or at least safely).

Would love some insight from anyone who's done this kind of content before.