How to control rival car in Racing track?

When i drive a car along the racing track, i want other two or more cars (except the one i will control myself with arrow keys) randomly run just across the road at a given speed and turn automatically at crossroads? Can anyone give me any hint to do that? What is the way? What key word should i Google to learn it? Please help.

‘Way point system’ is the solution!!! Yeah i have got it and successfully applied it, it’s amazing !!