Thanks for your very interesting question! Like all members of the House of Representatives, the Prime Minister is expected to act in an appropriate and orderly manner. And, like all other members, the Prime Minister can be removed from the House if they do not.
Under section 94a of the House of Representatives Standing Orders, the Speaker of the House of Representatives can make a disorderly member leave the chamber for one hour. During that hour, the member cannot enter the chamber. This means they cannot participate in the meeting and cannot make a speech or vote.
No prime minister has ever been removed by the Speaker for disorderly behaviour.
In the unlikely event that a prime minister was removed from House of Representatives, the Deputy Prime Minister or another minister would fill in for the Prime Minister.