First time credit card?

So I’m a first time credit user

I have no idea where to start and I want to build my credit.

We’re trying to fix my s/o’s credit so his name is under all the bills.

I heard that you have to be approved for a lot of cards so I’m thinking of just opening up a target card or something.

Or should I try to apply for a student card?

Or should I apply to a credit card from my bank?

Or should I try to do payments on a car?

I’m so confused as to what to do anyone have any tips for me LOL