You are not required to file your power of attorney unless you are using it for a real estate transaction. Real Property Law §421.
You can also file a copy with the County Clerk’s Office if you would like to be sure you can obtain copies if needed.
Remember, your power of attorney cannot help you if it cannot be found. Also remember if you want to cancel or revoke your power of attorney, you will need to notify any of the places where you filed it.