Hiya!

Well.... who was first there: the chicken or the egg?

Cockerels are still needed to get the fertile egg that will eventually and with a bit of luck and preservance of Mrs Hen turn into a brand new chick.
If you want to breed your hens and wake up every morning before 5 am, then you will need a cockerel.

If you prefer only the daily breakfast egg, your hens will manage this on their own

Hope, this helps?