You just got a cat.

Every checklist online is longer than the last one, and most of them are trying to sell you eleven things. Here is the short version. You can add to it later once you know her.

What you actually need

Food and water bowls
Shallow and wide. Deep bowls press on whiskers and some cats hate it enough to eat less.
A litter box and litter
Unscented, clumping. Scented litter is for you, not for her, and plenty of cats avoid it.
A carrier
Get it before you need it. Buying one the morning of a vet visit is how the first trip goes badly.
A scratching surface
One vertical, one horizontal. She will pick a favorite and you cannot predict which.
A hiding spot
A cardboard box works. For the first week she will want it more than any bed you buy.
Nail clippers
Start clipping in week one, before it becomes a fight.

What you can skip for now

— A cat bed — most cats pick their own spot and ignore the bed entirely.
— A big cat tree on day one — wait until you know where she likes to sit.
— A pile of toys — buy two, see what she likes, then buy more of that.

One thing worth watching

Cats have a weak thirst drive and often do not drink enough on their own. Low water intake over months is linked to urinary problems, which are common and expensive. You do not need to worry about it this week — just put water somewhere away from the food bowl and keep an eye on whether she uses it.

Anything that looks like a health problem is a question for your vet, not for us.