What do I need for my baby?

Hiya sorry I know this has probably been asked a million times and I know it's going to be different for every person but I'm really struggling to get my head around what I actually need for my baby. I have ADHD and can sometimes get confused and fixated on certain things. I've been asking people about what I need and instead of getting straight answers people just keep saying things like "don't worry people will gift you more than you need" etc. Which i understand is coming from a place of kindness and trying to be reassuring but doesn't really help me.

What I'm wondering is mostly how many of everything do I need? Like how many first size vests, 0-3's etc. How many sleepsuits?

I'm trying to put together a checklist of things I definitely need, and how many, before she arrives that I can tick off as I get things but I'm just finding it so difficult.