Beyond human lifespan there is no maximum time a justice may serve, but is there a minimum requirement that a justice is required to serve?
Not in the Constitution. Justices "hold their Offices during good Behaviour".
In the tradition and convention that governs the actual function of the US government, Justices can resign their office. There is no notice period and a Judge could resign as their first and only act in the office. It has never happened, neither in the supreme court nor in any inferior court.