How do interchanges work under the International Laws?

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Under Section 4 of the International Laws (April 2023):

Each team may use interchange players, provided their names are made known to the referee before the match starts.
An interchange is only effected after a player has left the field. The replacement takes the field immediately, in an onside position, with the permission of a Touch Judge or Interchange Official.
League governing bodies may choose either unlimited or limited interchange for their competitions, so the number allowed is set by the competition.
A player cannot be replaced during a play-the-ball, except a player replacing an injured player who has left the field, or when play has been stopped because of injury.
If an interchange happens when a kick at goal is about to be taken, the incoming player cannot take the kick.
If a player is bleeding excessively, the referee directs them to leave the field for attention or to receive medical attention on-field. If they are replaced, the replacement counts as one of the interchanges.
A "free" interchange is allowed when a player is fouled and injured by a player who is dismissed, sin binned or placed on report, but only if the injured player is immediately replaced. If the injured player later returns to the field, the interchange is then counted.
A team must have at least 9 players or the match is terminated for safety reasons. Players in the sin bin count as participants, but dismissed players do not.