Ordinarily, meetings in OrigamiUSA's shared Zoom room do not have a "host". This means that anyone can join the meeting, anyone can share their screen, and so forth, but the success of the meeting relies on everyone behaving nicely (and muting their microphone when they're not talking to limit background noise that everyone can hear).
It is possible, though, for someone to take on the role of "host", which means that person can control the meeting space: they can choose who can share screens, mute or unmute individuals, and basically run the meeting. This is a good option if one person is presenting and everyone else is just watching.
In order to become the host, you need a host key. To get this key for the meeting, you will need to email the COGS Online coordinator at cogs-online [at] origamiusa.org and request the host key for your meeting. Once you have it, here's how you'll use it.
When you first start up the Zoom app and join the meeting, you'll see the standard screen, something like this. Click on the "Participants" link at the bottom, circled in this image:
That will open a window on the right side, showing everyone attending the meeting, and some new buttons at the bottom. Click the "Claim host" link (circled in red).
A new window will pop up, asking you to enter the host key. You'll do this with the key you received from the coordinator.
Once you've done this, you'll see additional controls at the bottom of the screen, as shown here, that will let you control the meeting and individual participants.
For more information about what you can do when hosting a meeting, see Zoom's own documentation and videos.