An electronic apparatus for performing an electronic blackboard function comprising: a display; a memory configured to store at least one instruction; and a processor configured to execute the at least one instruction, wherein the processor is configured to, by executing the at least one instruction: based on a first user input, which is a drawing touch input, to control the display to display a first drawing according to the first user input on a first layer for displaying a graphic, based on a second user input for receiving an image from an external device, to control the display to display the image on the first layer, characterised in that the processor is further configured to, based on a third user input for generating a second layer, generate a second layer for performing a second drawing, wherein the second layer is overlaid on a partial area above the first layer, based on a fourth user input, which is a drawing touch input, control the display to display the second drawing on the second layer according to the fourth user input; wherein the electronic apparatus is configured to: display the first drawing included in the first layer and the received image on the display as a full screen through a composite process; and display the second drawing included in the second layer directly on the full screen without the composite process. a display; a memory configured to store at least one instruction; and a processor configured to execute the at least one instruction, wherein the processor is configured to, by executing the at least one instruction: based on a first user input, which is a drawing touch input, to control the display to display a first drawing according to the first user input on a first layer for displaying a graphic, based on a second user input for receiving an image from an external device, to control the display to display the image on the first layer, characterised in that the processor is further configured to, based on a third user input for generating a second layer, generate a second layer for performing a second drawing, wherein the second layer is overlaid on a partial area above the first layer, based on a fourth user input, which is a drawing touch input, control the display to display the second drawing on the second layer according to the fourth user input; wherein the electronic apparatus is configured to: display the first drawing included in the first layer and the received image on the display as a full screen through a composite process; and display the second drawing included in the second layer directly on the full screen without the composite process. based on a first user input, which is a drawing touch input, to control the display to display a first drawing according to the first user input on a first layer for displaying a graphic, based on a second user input for receiving an image from an external device, to control the display to display the image on the first layer, characterised in that the processor is further configured to, based on a third user input for generating a second layer, generate a second layer for performing a second drawing, wherein the second layer is overlaid on a partial area above the first layer, based on a fourth user input, which is a drawing touch input, control the display to display the second drawing on the second layer according to the fourth user input; wherein the electronic apparatus is configured to: display the first drawing included in the first layer and the received image on the display as a full screen through a composite process; and display the second drawing included in the second layer directly on the full screen without the composite process. display the first drawing included in the first layer and the received image on the display as a full screen through a composite process; and display the second drawing included in the second layer directly on the full screen without the composite process.