Get Lamp is a phrase often used in the game Adventure, where the player character needs a lamp to navigate dark places. To "get lamp," the player must find and acquire a lamp item.
Basically, in the game, it's really dark in some areas, so you need a lamp to see where you're going. To get a lamp, you have to find one somewhere in the game. Once you have the lamp, you can explore the dark places and see everything around you. So getting a lamp means finding the item you need to see in the dark.