My two Nissan Titan XDs had factory installed Tekonsha Prodigy break controllers. I hope your Armada also has one. It should be within easy reach of the steering wheel and have a digital readout with a red dot (or two) when not connected and a "C" when connected. It should have a lever that can be used to manually engage the trailer brakes and an up/down arrow to adjust the braking level. Mine was dash mounted on the right side of the steering wheel.
On some of my other Nissans, the trailer tow package included the wiring but not the brake controller. There was a plug under the steering wheel (attached to the steering column) that had about six pins. I bought a Tekonsha Prodigy brake controller and the adapter wire from Tekonsha to insert directly into that Nissan plug attached to the steering column.
Bottom line, look for the brake controller push lever and digital display on the dash. If you have one, you are all set to tow.
2018 GT27Q, 73 nights 12,177 miles, 600W Solar - 110kWh, PD4655L, 6V Batteries, Blue Ox, 16" tires, 2019 F250 PSD
Sold: 2017 FC25FB, 316 nights 40,150 miles, Propride, 400W Solar - 200kWh in 216 days
2013 Casita SD17 89 nights 16,200 miles