The pool of potential jurors are taken to a room where they sit until their jury summons number is called.
In my case that was to one of two large rooms where a video feed to the courtroom was set up. It revealed the judge and you could hear the lawyers selecting jurors.
You stay seated until your jury summons number is called.
The would call about 18 numbers at a time and potential jurors lined up in the order their summons was called. The entire group was called into the courtroom where you either speak to the judge or proceed to be examined by the prosecution and the defence.
You speak to the judge about any reason you cannot be on the jury. You will either be excluded as a potential juror for the specific trial and sent back to the jury pool or dismissed for the entire day if your reasons for not attending will be problematic for all trials they are selecting jurors that day.
The number of trials that they will be seeking jurors for will change from jury selection to jury selection. As the time, the court had three trials that they were looking to staff.