What drone brood looks like in a normal hive & where it should be located
Roughly 10% of the brood in a hive is typically drone brood. Since drones require a larger cell to develop in than workers, the bees must build special cells that are larger in diameter than worker cells. They typically do this in continuous sections along the edges of frames, between hive boxes, or on sheets of comb the bees draw out themselves in spare space between frames or between on the inside edge of the box. The 2 pictures below show normal drone brood.
What you should not see is drone brood randomly scattered and mixed in with your worker brood. That is often the sign of a failing queen. See “How to tell a hive needs to be requeened”