I recently bought this 2000 Lincoln navigator and the knob does not have the option to put in 2wd only 4awd 4H and 4L
And I want to know where do I keep for daily driving?
Because the 4x4 light on the dash stays on all the time
You need to drive in A4WD. That is rear wheel drive. When the system senses slip at the rear wheels it will apply torque to the front wheels to help until the rear regains traction. Use 4H & 4L off road only as that is full time 4wd.
Use A4WD daily on hard surface roads, it acts like a differential between front and rear drive shafts, think of it as simply "All Wheel Drive". The 4H and 4L lock the front and rear driveshafts together, bad for hard surfaces with good traction.