Question to experienced mommies

This is my first pregnancy and I'm not too far along. Where I come from baby showers aren't exactly a thing, people give you gifts after the baby is born, not before because of superstitions I think. And I have no idea what is most needed and in what quantities. Do i need 20 onesies? What else is absolutely crucial and necessary for the first three months. Please help! And the more details the better 💚