one baby chick
Chicks really need to have other chicks. Not just ducks. I'm surprised that someone sold or gave you just one chick. If you can't have at least two, preferably three, chickens then it would be best to re-home the poor thing.
And if I find a way to keep him and get him a friend, would getting another boy or a girl be better for him?
Do you know for sure (as in he is a sex-linked breed) that the chick is male? Anyway, chickens are social creatures which is why numbers of three or more is best so that if one dies there isn't a singleton left. If it is a male, I'd get a male since a single hen would get over-bred which isn't good for her. Males do well together when there are no hens to fight over usually. So get a couple males if he is a male. But if the chick is a female, get a couple more hens.
Can you take return the chick where you got it? You can always put up an ad but know that once the chick is out of your possession, you really have no control over what happens to it. Even if it does become food, the quality of life will be better if it goes to a home where he/she isn't a chick alone or among only two. I have processed a couple of my own chickens for various reasons but I have always done it with the knowledge that it lived a much better life than it would have as an industry chicken with lots of room to run, healthy food, social stimulation, and a happy life. Regardless of the length of time, isn't that really what you want the chick to have?