I think this type of help for others is terrific and appreciated. Specifying a region for the green screen offers considerable benefit when you want to position a graphic, such as a chart or diagram, as you explain research findings or a concept.
The next thing that needs to be understood is identifying a specific area of the image dropped into the green screen area as "active" in post-production. That means someone viewing it can touch or click on it and be taken to another piece of content, such as a description or added details. If possible, this is something I wish to understand as it will make the video dynamic for viewers and also tell me, as the producer, what people find most important or interesting for future content segments.