If you are in need of some inexpensive or free stock and video imaging, these site should help you out:
Video
Coverr - Large library of short videos suitable for backgrounds on websites or on-line meeting. Most material is free.
Images
Unsplash - Unsplash has a great variety of background and stock images. All are free downloads, but you will need to create an account before downloading. The site contains contributions by professional photographers. When you complete a download, you are asked to share on any social media or eMail about the picture you selected. It sort of an open gallery where photographers can show off their work.