Just adding to Ruben's reply. They are not giving out appointments but there are some things you can do as a walk-in. You must have whatever documents you may need by the time you get to a window. There are no in and outs. If you forget something in your car, you must go back to the end of the line.
Unless you already have an appointment, there only giving same day appointments. Fill out the Get my Real ID form on www.dmv.ca.gov and bring your conformation number to the office. You will need that conformation.
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