The cause for vomiting
needs to be known at first to start with any treatment.
Till then take Arsenicum alb 200, 4 pills thrice a day and Ipecac 30, 4 pills twice a day and report thereafter for further treatment.
Take light diet
like khichdi or dalia, ORS 3-4 times a day if vomiting is more, be hydrated, take rest
And revert back for further treatment.