Above the list of participants is the "Shared Notes" field. All participants can write in it at the same time, e.g. to take minutes of the meeting. If you are familiar with Pad (i.e. Etherpads), this should be nothing new to you.
Watch out: Your shared notes will disappear once everyone has left the meeting, so make sure to back them up beforehand if there was anything important in them.
As the moderator of the meeting (see below for roles and permissions), you can also pin the shared notes to the whiteboard so that everyone can see them large, or convert the notes into a presentation to show the status of the shared notes at that moment (via the three-dot menu to the right above the shared notes). You can then no longer change the text in the presentation, but you can decorate it with the whiteboard tools (see below). The best thing to do is just try it out for yourself.