Newborn checklist.

I have no idea what I need and I'm looking on Pinterest but a lot of the checklist have items that a newborn baby does not need .a lot of this stuff seems to be for a toddler or something. I have never been a mother and I'll be a single parent ,so I'm trying to invest in the stuff that I absolutely need in the beginning ,not down the line .any must have suggestions??..and it's little things, like I don't know how many onesies to buy for example, like does a baby wear one a day, or do you change them many times a day .I don't know 😭