Start by clicking in the users who are present. If they are not present but have notified an absent, you can mark this. Then you can choose their function at the meeting and who will be the secretary and one or more adjusters (also mark the chairman as adjuster if he is to adjust).
Board members are always listed from the start, but both these and other names can be removed completely from the attendance list by clicking on the icon with three dots and selecting "Remove" on the far right.
Should additional people be added, press the "Add person to meeting" button at the bottom left.