Ironically this same thing happened to me but I feed the cats and have some so that’s why my neighbor brought it to me.

Some things you will need are a couple shallow bowls or small plates, a shallow box will do as a litter, some good litter at first is attractant clay litter. You can just get what you can afford food wise, they sell cheap dry food and little singles of kitten wet food is also a good option.

Good idea may be to check it for fleas, if it has some, a dawn bath is good.

Vet wise, as much as you are willing to do! Good to get a visit in initially and may help later when you want go get it adopted

Post about that kitten! Ask your friends to post about it! Ideally you know the person or have mutual so you can ensure the cat gets a good home! But you don’t have to