The coding for this project occurs in two stages.  First, you need to find out the unique identifier of your RFID card so that you can enter it into the code to make your robot move.  Start with this code, which will print the identifier to the serial monitor where you can copy it.

 

Once you’ve got the identifier for your RFID tag, use the code below and enter the identifier into line 64.

This code is written to make the robot move forward when it sense the correct card.  You can change that code, or combine this code with other sensors to make the robot behave however you choose.