You can start off by reading Suzanne's Primer in one of the stickies at the top of the webpage. It also contains the links to diff. websites you should know.
There are also lots of threads here that can answer all your Q's. Most of the active and recent ones are on the first 3 pages of this forum. There is also a Search Button on top w/c you can use much like any internet search engine.
To give you a headstart in your readings.. you only apply to NY State if you really have plans to work in there. It requires CGFNS' Credential Evaluation Service (CVS) and not the CG exam or the Certification. The CVS process takes quite a long process for various reasons. Anywhere bet. min. of 8 mos. to up to 12 mos or more depending on diff. circumstaces. However, if this is where you want to work, there are no other way to apply but apply directly for CVS and getting licensed to another state and endorsing to NY will not do any good and will in fact take you longer because you cannot escape the CVS.
That is for now, I recommed reading Suzanne's Primer 1st then read the other threads here regarding your query. Your Q' has been asked very recently and answered very recently as well. You don't have to look far either. It's on the 1st 2-3 pages of this forum.
Happy reading on the stickies and diff. threads about NY and other common state BON where Foreign RNs apply to.