1. An electronic apparatus, comprising: a processor, configured for executing an operating system and loading a basic input/output system (BIOS) to execute an initialization program; and a touch display module, comprising: a touch display device having a virtual input area, wherein the touch display device generates a touch event when the touch display device is touched; and a touch input controller coupled to the touch display device and the processor, the touch input controller receiving the touch event and generating a coordinate value according to the touch event, wherein, when the electronic apparatus has loaded the initialization program and the electronic apparatus has not loaded the operating system, the touch display module is defined to comprise a human interface device comprising a virtual keyboard, and the virtual input area displays an input interface comprising a plurality of functional key icons, wherein each of the functional key icons corresponds to a key of the virtual keyboard; wherein when the coordinate value is located in the input interface at a position corresponding to one of the plurality of functional key icons, the touch input controller transform the coordinate value into a corresponding functional code of the human interface device, and the processor executes a corresponding operation according to the functional code; and wherein when the coordinate value is not in the input interface, the touch input controller transmits the coordinate value to the processor.