Disk is stuck in a multi-disk CD player. How do

You didn't specify the make and model of the unit you have, but I can give you some basic steps that should help you resolve the problem based on past experience with other similar units.
First unplug the unit. Then remove the screws that hold the cover on the unit. Remove the cover. Any CDs that are not in their holding places that may have fallen into the unit, reach in carefully and remove them from the unit and set them in their jewel cases. If the unit was not ejecting the disk and it was stuck, check to see if the CD was perhaps stuck between the spindle and the arm that holds the CD to the spindle. That happens sometimes on CD players. If that is the case, you should be able to remove the CD anyway but you have to be careful and not be too forceful to any mechanisms involved. I hope that helps.