Green/Red detector and button controlled car (BASYS3/VHDL)

Hi, I am a 2nd-year ee student, and I need to make a term Project. With 
BASYS3 by using VHDL.

My purpose is constructing a car which can be controlled with the 
buttons on BASYS3 ( I think I need Bluetooth module for it to RC a car). 
In addition to that my car should stop when it sees red ( i think I 
should use a color sensor for it) and should not work until it sees a 
green. These “red” and “green” can be anything like green cubic toys.
This color sensor does not have to be mounted on the car, but it would 
be better if it is.

I have very little information about basys3, vhdl, sensor design, etc. 
(this is my first course in ee I was learning principle courses like 
math, phy, cs )

I would appreciate any help.
Thanks.