A knowledge base article about Zoom: What to do when host controls are not available provided by the UC Berkeley IT Service Hub - Knowledge Portal
If you find that your host controls are not available during a meeting, it could be that you are not logged into Zoom, so Zoom does not recognize that you are the official host. For accounts that are configured for 'Join before host', it is possible to run a 'hostless' meeting where all of the participants join but none of them are the host and therefore the host controls are not available. Meetings without a host cannot share screens, manage participants or record. 'Hostless' meetings are subject to a 40 minute limit.
Before starting your meeting, make sure you are logged into Zoom first.