Chickens are actually hermaphrodites, and different temperatures at the time of incubation will have an effect on the development of the male and female organs in the future. Nowadays, they are all factory-produced chickens, and the incubation temperature is well controlled, so the general chickens are female.

No need to castrate.

Generally get the hen as a breeder is not very useful, the general chickens are special male chickens with the hen with the eggs produced only used to make chickens.