What is the life cycle of a nit?

Dr Sarah Jarvis

Head lice look like tiny little ants, and the eggs look like white spots clinging to hair strands. Nits look a lot like dandruff; in fact it's more or less impossible to tell the difference. Lice feed from the blood on your scalp, and it is the bites (and your skin's reaction to the bites) which make you itch.

https://patient.info/health/head-lice-and-nits