"I want to share this news with the public."
Translation:Je veux partager cette nouvelle avec le public.
j'ai envie de means i feel like...as one friend would say to another about going for one type of movie over another; je veux = i want (really would like). Of course it depends on context; and they are interchangeably used often... except when the context demands one or the other... here it is a stronger sense of wishing/wanting to share the news.... so veux. Maybe others can provide better answer.