An electronic device comprising: a housing; a flexible display at least partially exposed to an outside through the housing; an actuator for changing a size of an exposed area of the flexible display; at least one processor; and memory storing instructions that, when executed by the at least one processor, cause the electronic device to: based on receiving a first user input on the flexible display, in a state in which a first part of the flexible display is exposed to the outside, for a sliding operation of the flexible display to further expose a second part of the flexible display to the outside, control the flexible display to display an indicator in at least part of an area of the first part of the flexible display corresponding to a slidable edge area of the flexible display to inform a user about a location of the slidable edge area, wherein the slidable edge area is an end area of the flexible display which moves in an outward direction from the housing, irrespective of a content display direction, based on the sliding operation, detect an interference factor interfering with the sliding operation of the slidable edge area, based on detection of the interference factor, provide a first feedback indicating that the interference factor exists, and based on detecting that the interference factor is removed after the first feedback is provided, control the actuator to expose the second part to the outside by sliding at least part of the flexible display including the slidable edge area. a housing; a flexible display at least partially exposed to an outside through the housing; an actuator for changing a size of an exposed area of the flexible display; at least one processor; and memory storing instructions that, when executed by the at least one processor, cause the electronic device to: based on receiving a first user input on the flexible display, in a state in which a first part of the flexible display is exposed to the outside, for a sliding operation of the flexible display to further expose a second part of the flexible display to the outside, control the flexible display to display an indicator in at least part of an area of the first part of the flexible display corresponding to a slidable edge area of the flexible display to inform a user about a location of the slidable edge area, wherein the slidable edge area is an end area of the flexible display which moves in an outward direction from the housing, irrespective of a content display direction, based on the sliding operation, detect an interference factor interfering with the sliding operation of the slidable edge area, based on detection of the interference factor, provide a first feedback indicating that the interference factor exists, and based on detecting that the interference factor is removed after the first feedback is provided, control the actuator to expose the second part to the outside by sliding at least part of the flexible display including the slidable edge area. based on receiving a first user input on the flexible display, in a state in which a first part of the flexible display is exposed to the outside, for a sliding operation of the flexible display to further expose a second part of the flexible display to the outside, control the flexible display to display an indicator in at least part of an area of the first part of the flexible display corresponding to a slidable edge area of the flexible display to inform a user about a location of the slidable edge area, wherein the slidable edge area is an end area of the flexible display which moves in an outward direction from the housing, irrespective of a content display direction, based on the sliding operation, detect an interference factor interfering with the sliding operation of the slidable edge area, based on detection of the interference factor, provide a first feedback indicating that the interference factor exists, and based on detecting that the interference factor is removed after the first feedback is provided, control the actuator to expose the second part to the outside by sliding at least part of the flexible display including the slidable edge area.