Characters who sit around and do nothing will be judged as not interesting. This is especially true when we first meet them - after all, who wants to read about someone who does nothing? It's very important that when your character first turns up they are doing something.
But what? The temptation is to show them doing something dramatic - rescuing babies from a burning building perhaps, or foiling some dastardly deed. I once read the opening to a first novel which started with a gin palace being blown up, killing all the occupants. It was, I suppose, exciting but given that the only thing that defined the characters was the single quality of being in smithereens, it was hard to engage with them.
Instead, show your character doing a straightforward action. One of the best actions to start with is to show them making a choice, even if it's something as ordinary as choosing between Braeburn and Pink Lady apples at the supermarket, but any action will do. The thing to avoid is the character talking or thinking about doing something. To quote another saying: Actions speak louder than words.