The Buffalo Federal Detention Facility in Batavia, New York is an immigration detention center, and it operates differently from a standard county jail or state prison. The Batavia Immigration Program provides universal legal representation to people detained there who are facing deportation and cannot afford private counsel. It functions as a public defender model for immigration proceedings and is funded through the New York State Office of New Americans. Anyone detained there who is financially eligible and does not have an attorney should ask about this program, because having legal representation in deportation proceedings makes a substantial difference in outcomes.
On the work program question: any work program inside a detention or correctional setting is a good thing for the person in it. Working gives a detainee purpose, structure, and something to focus on during what is otherwise a period defined by waiting and uncertainty. The alternative for those not working is long stretches of boredom that weigh heavily on mental health. Participation in work programs, even voluntary ones with modest compensation, is consistently reported by people who have been through detention as one of the things that made the time more bearable.
If your person is at Batavia and is interested in the voluntary work program, they should ask their housing unit officer or counselor how to get on the list.