Only the acting host in a Zoom meeting can make someone else a co-host or the host. The acting host is either the person who created the meeting or, if that person isn't present, the first alternative host to join the meeting.

There is no limit to the number co-hosts in a meeting, but there is only one acting host.

Elevate a participant to co-host or host

1. Either the host or an alternative host, start the meeting as the host
2. In the meeting controls, click Participants 
3. In the Participants list, hold your mouse over the name of the participant who is going to be a co-host or host, and select More
4. Select Make Co-Host OR select Make Host
   Note: If you make someone else host, you are no longer the host of the current meeting as there can only be one acting host
5. Once a participant has been made a co-host (or host), they'll have access to the co-host (or host) controls.