You must be the host of the meeting to make a meeting participant a co-host. There can only be one host, so if you make someone else the host you will become a participant. There is no limit on how many people you can make co-host.
Steps
In Zoom, in the participant's participants pane, to the right of the participant that you want to make a co-host, select More (the three dots), and then select Make Co-host.
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