Hey Izzy
Thank you for looking for advice before rushing out to get a bird. Well done.
It is always hard getting a bird in school. Schedules change often and normally you also want a social life. In terms of time before the bird feels neglected, it all depends on the bird. GCC are very attached and physical with their friends. It will be difficult for a GCC to be happy for hours on end alone; some develop screaming behaviour calling out to their flock all day long. Each bird also has their own personality, between my two parrotlets they are completely different personality wise. Some birds are more needy of their people.
@tka normally shares a nice post about the time reality of bird keeping and student life.