Display device and operating method thereof

A first display device comprising:

• a display;
• a communication unit comprising communication circuitry;
• a memory storing one or more instructions;
• and
• at least one processor, comprising processing circuitry, individually and/or collectively, configured to execute the one or more instructions, and to control the first display device to:
• control the communication unit to communicatively couple to a second display device;
• control the display to display an item including information about the second display device and information about an external device connected to the second display device;
• control the communication unit to, based on an input to select the item, request the second display device for image data corresponding to the external device, and receive the image data from the second display device;
• and
• control the display to display the received image data.