During an arraignment, all charges against the defendants will be read to you by the judge unless an attorney waives reading of the complaint.
Afterwards they will enter a plea and custody status may be discussed. Before all this happens the judge will ask if they can afford an attorney. If they cannot he will appoint counsel for you (usually the public defender).
Depending the arraignment certain future dates will be set. A final very important question at arraignment is whether they are willing to give up the right to a speedy trial. Since they are in custody they may not want to ( very serious crimes like this 911 attack require more time to prepare than speedy trial deadlines allow).