A road following car

Hello. Am a new programmer with zero information and as my first school program i am willing to make a car that autodrives, the problem am having right now is how to make the car follow a specific road, for example a road with three passages and the car is in the middle how can the car detect if the road will be straight or there will be a turn coming. I thought about line following but that isn't an option, let's just say lines aren't available so any suggestions for this one? Any help would be appreciated and thank you.

Are you talking about real roads? Or a model which simulated real world road conditions?

If it is real roads, you just need to follow in the footsteps of the companies who have done it successfully.

Massive video processing is a large part of the requirements.
Massive logic is another.

Neither one of these are available to the arduino.

as my first school program

Since you are just starting out, it is very important to work through the examples that come with the Arduino program development software, in order to learn the special features of Arduino and the programming language.

Learn to blink an LED without using delays, read a voltage, sensor or switch, control motors, etc.

If you don’t, expect endless frustration and confusion.