What region did you set your route to when you created it? There are no carz in the "Default" region.
As for your second question: Not directly. The "carz" system in Trainz is quite obviously intended mainly as "background" scenery (this is a railway simulator after all) that moves along roads and stops at railway crossings. Making the carz system work more realistically--by making the cars' turn directions at road junctions practically random and making them stop at traffic signals--is possible, but is complicated.
However, creative Trainzers can lay down invisible railway track (which is visible in Surveyor, but invisible in Driver when you are actually driving your things) and place drivable cars, planes, boats, etc. on that invisible track to drive them along it. Since these drivable objects are locomotives/trains to Trainz, the path that these drivable objects can take is fixed to the invisible track, just like the path of a train is fixed to the railway track. Just like railway track, the invisible railway track can have junctions, so the drivable objects can take different paths, but those paths are still just the fixed invisible track. So basically, there is no steering like you would find in a real car, boat, plane, or whatever; the object just follows the fixed invisible track like a train. Still, interesting drivable setups can be created. Note that since drivable objects are considered by Trainz to be locomotives/trains, these drivable objects are totally seperate from the carz system, so you can drive drivable cars right trough regular carz and they will not even notice!
For your interest, older versions of Trainz (such as what I use, TRS2004) allowed users to type in the key combination Alt+C+A+R+Z in Surveyor and then click on one of the carz on a road. The camera would then snap to the top of that car, giving the user a view from the top of the moving car, until either the user deliberately quit the feature by pressing the Esc key on the keyboard, or the car reaches the end of the road and is this deleted, returning the user back to normal Surveyor. I am not sure if this feature still exists in the latest versions of Trainz or what different key combination might be assigned to it in such newer Trainz versions, but it is pretty cool.
Regards.
