The green color will be replaced by Zoom with your selected image or video. If not, you need to use a solid-colored screen or choose a location with a green wall. If your computer meets the requirements, Zoom can apply the background without the help of a green screen.
For example, the ability to display a custom background in your Zoom meetings. The free offer is quite generous, not to mention that you will also get dozens of other features. Plus, there is no limit on the number of meetings. Up to 100 participants are allowed to join a meeting, a group meeting can be held up to 40 minutes, and you can have a video call with another user in a one-in-one meeting for 30 hours per session. The free plan should be good enough for most people.