I'd start by going through everything you have and then make a list or registry with obvious things you know you will need as soon as baby is born. Winter clothes, diapers, wipes, socks, and mittens and hats, fingernail clippers and baby bath tub. Then as you go you can add the bigger stuff you may need. That's kind of what I did, I have a 16 month old and thankful same gender so I have mostly everything I need just the smaller stuff.
I just made a baby registry and told everyone that this is what I need and it doesn't have to be exactly what's on the list just similar stuff so everyone has an idea of what to get for baby.
Yeah, essentials being a place for baby to sleep, a place to wash baby a few outfits and swaddles and diapers. I second if you have a local free group. Mine on Facebook has some incredibly wonderful moms that have been so generous!
Facebook marketplace baby buy nothing groups!!! Those go me so much stuff
As well as groups for free stuff / baby stuff or kids stuff just free anything
Honestly I would just tell everyone diapers and clothes, And the bigger stuff look on like Facebook marketplace for things that are still in good condition and cheap or even free. I'm in a few mom groups from my area and they are always getting rid of nice things for free and stuff.