Where you are located?
Are you sure you have a hen? Unfortunately many people abandon cockerels or roosters more often than hens. Have you seen any eggs?
What are you feeding?
Do you plan to get your bird a companion? Chickens are flock animals and are happiest with more of their own kind.
We would all love to help you and answer any questions you have if we had some more information.
Good luck with your new chicken!