The wattles you're referring to are fleshy, wrinkled skin that hangs beneath the beak of birds like roosters (male chickens). Roosters typically have larger wattles than hens, and this can vary depending on the breed.
In general, both roosters and hens have wattles, but the number you mentioned—three for roosters and two for hens—might be a misunderstanding. Most chickens, regardless of gender, typically have two wattles, one on each side of the beak. The wattles are part of the bird's reproductive anatomy and play a role in temperature regulation, as well as in mating displays and sexual selection.
The size and shape of wattles can also indicate the health and vitality of a chicken, with larger and brighter wattles often signaling a well-nourished and healthy bird. In summary, both roosters and hens typically have two wattles; the presence of three wattles in roosters might be a specific trait of certain breeds or a result of an anomaly, but it is not typical for chickens overall.