using hyperdia

hi my name is esteban from argentina, ill be in tokyo on noverber 5 th and i hope to visit many places. i have bought the jp ticket and i have some questions about travelling there. for exemple to travel from tokyo to narai i use hyperdia to know how ti get there, it say frm tokyo get jr chuo line rapid service to yotsuya, from there to takejr chuo sobu line to shinjuku there to take LIMITED EXPRESS AZUSA to shiohiri and then the jr chuo line to narai. the limited express azusa is property of jr ? or isnt a service from jr? do you know if in hyperdia the color green of the train is because its for only jr lines? thank you so much i hope your answer. excuse my englis isnt enough good