Question

Can the chairman add agenda items during council meeting?

Answer 1

Only if the item is permitted under the standing orders. Which would, typically, be limited to items that were statutory - electing a chairman, or required action without notice - asking someone to leave the room.

General matters should be correctly notified on the agenda, any spending or binding action on the council would be void. (Except where specifically allowed in the standing orders).

Answer 2

"Somebodyelse" is quite right, and if your standing orders are based on the NALC model (most are) then there is a list of the motions that can be put without prior notice.

They also include a variety of procedural motions, such as a motion to move to the next item of business (to curtail something the council thinks has already taken enough time) or the creation or disbandment of a committee. Essentially, they are all matters that are to do with the running of the council, and have no external impact. For example, creating a committee does not in itself decide anything.