When the jury sends a question, if it's to do with the evidence, the judge discusses it with the prosecution and the defence and they make their cases for how they want it answered. The judge is the arbiter of disputes between them, if any, and then the jury is called for and the judge gives them their answer.
If jurors send a question during the trial you will see the same thing happening, he will send the jury to wait outside the courtroom if they need to discuss it without the jury being there, and then call them back in to court, or sometimes it will be a question they want to ask of the witness, in which case it will be asked, if approved.
Juries do not have written copies of agreed witness evidence or any witness evidence. The evidence is verbally given and the jurors may make notes if they want to.