Just to add to @OldUsergreat answers.
* 90 days is not the same as 3 months. Use 90 days.
* In NJ, the field offices in Newark or Mt. Laurel are most likely to give you a combo interview and same day oath. In Newark, if you are extra prepared, after the oath, you can update your Social Security info in the same building and then walk out and apply for a US passport in the post office next to the field office. Basically everything in one day for the ambitious ones. Good luck.