An example of a 1280x720 mp4 video as hero background - compressed videos of a small size are best for page speed.
This can be achieved by you sending me your video, and I can upload it. Another way my clients do it, is they have a youtube channel for their business, and upload the videos there, and I can display the video directly from youtube.
An example of a youtube video as hero background or can be displayed anywhere on the web page - I have chosen to only show 3 minutes of the video. I can set a start and finish time.
This is the same video but instead of playing in the background, I can add it on page, which give the viewer control over things such as the sound, pause button, etc.