what category does my character go into?
Supporting Characters are characters primarily intended to support the development and growth of other characters. They do not have personal plots of their own, and their character development is not a focus. You can read more about supporting characters here. Supporting Characters always go in the Supporting Character forum, regardless of whether they're a student or otherwise.
Students are characters on Manta Carlos who are attending Starlight Academy. Students who are being home tutored, or who are attending the police academy are not considered students, and would instead go in citizens. Being a student takes priority over being a citizen.
More information on students.
Staff are characters on Manta Carlos who work as faculty for Starlight Academy. This includes both teachers and non-teachers such as librarians, custodians, school doctors, etc. If a character has a civilian job and a position at Manta Carlos, they're considered staff.
More information on staff.
Citizens are everyone else, the people who live on Manta Carlos but who are not either a student or staff of Starlight Academy. Citizens will generally have a job, although a job is not mandatory to be a citizen. Characters who would not legally be considered citizens are still placed in the citizen category.
More information on citizens and businesses.