The OOP will be granted for a period of time of six (6) months up to one (1) year. If, at the end of that time, you feel like you still need protection, you may file a "Motion for Extension of Order of Protection." The Court can extend your Order of Protection for "good cause"--most judges say that "good cause" means that the Respondent violated the Order of Protection at some point or something else has happened since you were given the Order. The Clerk of Court will have the paperwork to extend the Order of Protection.
If you don't file to extend the Order, and you don't have another family court case with a restraining order (divorce or custody), then the Order of Protection and everything in it will go away (including child support, custody, etc.).