Hi Amrita,
Its good that you want to do US (CPA). for scope, i Can say that with CPA you can't practice in India. However, it is recognized well in a MNC and besides this, if you are not doing CA, then i recommend you to go for that.
Also, for CPA, you have to visit US for the exams. laso, coaching is available almost in all metro cities in India, along with the study materials and sample papers.
But Before joining, i must say you must go through all the details on the site > www.aicpa.org. Especially, check the eleigibility requirements for doing CPA. There are very strict requirem,ents as to the study hours and so.
Also, for CPA, in US you have to register yourself with any one of the states with which ur eleigibility meets. So check for it before taking any decisions. Also, consider the cost of the exams and the cost in visiting US.
If you can crack it, then it is a good course but it is sure, you have to work very hard for it.
Best of luck.