Store 4 different values in a byte

Question

I have an assignment to do, but I have no clue where to start. I am not expecting and definitely do not want answers in code. I would like some guidance as in what to do because

Answer 1

Have you read about bit field?

struct s {
  unsigned char engine_on : 1;
  unsigned char gear_pos : 3;
  unsigned char key_pos : 2;
  unsigned char brake1 : 1;
  unsigned char brake2 : 1;
};