My 2007 is stuck in reverse and wont start what is wrong with it?

Help me plz someone i dont know what the part is called

There is a Detent Switch that registers the position of the Shifter, and turns on the Indicator Light on the Dash to tell you what gear the Transmission is in. If the Detent Switch isn't registering the correct gear position then the car won't start because of the Neutral Safety switch isn't engaged. Try moving the Shifter into Neutral, and the car should start, but if it doesn't move the Shifter slowly forward and backward while you turn the key until you find the sweet spot that allows the car to start. There may be an adjustment on the Transmission that will allow you to adjust the Detent Rod enough to fix the misalignment, or you may have to replace the Detent Switch.

were is the detent switch located