Robot car with light sensor

We are working on a project that is a robot car with 3sensors detecting the track on the ground which are respectively left mid and right sensors.
However, we want to apply 3 states to the car, which triggered by the Left Mid Right sensors detect the 010.
Is there any coding reference?Thx a lot

Isn't the software the bit that you, as a student, should be providing?

I googled "Arduino line follower" and got over 600,000 hits.

Go take a look at some of them. I bet that more than a few use 3 sensors.
See if any of them fit your needs.

Or, review that code and then make a go of it yourself.
Break this down into pieces.
Write a sketch that reads the values of the 3 sensors and prints them to your serial monitor.
Wave the sensors back and forth over your track and see the different values that the sensors produce.
Write another sketch that makes the motors run. (I assume you have 2 motors for 'tank' style steering).

Then combine them and add some logic to drive the motors to keep the track under the center sensor.

We will be more than helpful if you run into problems with your code. Let us know how it goes!