its around 27 hours journey. as far as water is concerned you have to buy the mineral water from the station it self or you can carry your own big size water bottle ,thermus.
if you carefully see there is hault at every 1 hour till buxar.you can have some snacks at that time.carry a home made food for night and for day time you can have lunch at home it self before boarding the train. vegetables get rotten in the next day it self so you can carry additional pickles , small size jam bootle, fresh full size bread , carry some fruits as well. in moradabad you can take puri sabjee for lunch .