I’m not sure which file format to use for photos, videos and documents. Which is best? Also, please tell us the best file format for photos to be incorporated into Word! !
This totally depends on your use case. What do you need? The best quality? The smallest file size? The best compatibility? An open format? …
For videos, I would argue the best container format is MKV. It’s open and supports almost anything you throw at it.
Hardware support for MKV is also pretty damn good (although it might not work on Apple ecosystem devices).