Once you pass that exam, you are a Broker and you can open your own office immediately. Be aware if you are associated with a brokerage you'll get an Associate Broker license. You can arrange through the DOS for an independant Broker license. Good luck.
You need to call New York State Board of Realtor to find out about any laws regarding Real estate there. I know in California you must be a Real Estate Broker in order to open your Brokerage Firm.