How do I go about getting the bolt for the crank sensor off?

Hello, can you take a picture of what you're dealing with? Service info for the 3.5 liter shows the crankshaft position sensor on the back side of the engine, on the side of the engine block, it looks to be under the exhaust manifold. It states to unplug the knock sensor connector first that will help with access to the crank sensor plug. I'll post the diagrams of what service info shows, and if it's different than what you have, let us know. It should be just below the spark plug wires on the back side of the engine.

https://www.2carpros.com/articles/crankshaft-angle-sensor-replacement

It is on the back of the engine for the 3.5 liter, near the firewall and is easiest to get to from underneath. I would recommend driving the car up on some ramps if possible and blocking the rear wheels for safety. Don't rely on just a jack, always have jack stands under the vehicle as well. The crank sensor is under the exhaust manifold, so you probably won't get to it from up top.
Diagrams 3 and 4 below are the Crank sensor relearn procedure that will need to be done after replacing the sensor.