Hens can start laying eggs after they are 4 months old.
Hens lay eggs without a rooster. These eggs are not fertilized.
A hen can often lay one egg each day.
I feel like this is necessary, and will be said at some point -
Wait, start from the beginning. Which came first? The chicken, or... ?
The question is like to ask human came first or human sperm and egg came first.
And the answer may be not human sperm and egg came first or human came first. It's ape came first.
I see what you're saying. The question of which came first is interesting, but the idea of which came last is also interesting - the omelet.
I'm pretty sure that it depends on what your definition of a chicken is.