Summoning a God? I'm Summoning My Secret Identity!

My name is Shen Gui, and I'm a good-for-nothing. Literally. In our village, people awaken as Fire Gods and Sword Immortals. When my turn came, the altar strained for ages before conjuring a phantom that hugged a glowing, flat box and grinned like an idiot. The elders' faces turned green. Only later did I learn that the god I'd summoned was called “Elementary Schooler's Hand.”