General question

[LilJoe]

Pullet is female before she starts to lay eggs. Then she becomes a hen. A cockerel is a male before he matures to a rooster.
Bantam is small breed. The roosters have a reputation for being rather feisty. They aren’t necessarily aggressive but generally fearless and unaware of the fact that they are rather small. Then yes, other chickens come in standard size and large.

A pullet becomes a hen when she turns one year.. same with a cockerel becoming a cock/rooster.. (sorry I had to )