As the host in a meeting, you can manage the participants. By default, any participant in a meeting can share their video, screen, and audio. If you want to limit who can share their screen, video, and audio, we recommend using the webinar platform. For a full comparison of these options, see our meeting and webinar comparison.
additional instructions at: https://support.zoom.us/hc/en-us/articles/115005759423-Managing-participants-in-a-meeting