what is a birth plan ? Do I really need one ?

Marie✨ • Save the world 🌎 Raise a hippie 🍃 insta: Therealprincessterry
😳🙃 Hey ladies , Im a New mom I'm aware of some things but not all . Growing up with 3 younger siblings , I still need some help . If anyone can explain this to me or explain how to get started I will really be thankful ✨😊 thank you