cannot initialize a class member here!

I just looked at your original error statement. Since you are working in 'C' AND_NOT 'C++',(try and give a guy a hint, hmmph)get rid of the: 'class car{' and make a more ordered struct, including only the constants and variables, and no functions.

Like:

struct spCar{
              int spX;
              int spY;
            }
struct edgeLine{
              spCar strtPT1;
              spCar strtPT2;
               }

struct theShape{
             edgeLine line1;
             edgeLine line2;
             edgeLine line3;
             edgeLine line4;
               }

enum Shape{line, angle, triangle, rectangle, square, ...};

    edgeLine L1, L2, L3, L4, L5, L6, L7, L8;
    spCar pt1, pt2, pt3, pt4, pt5, pt6, pt7, pt8;


bool SetPoints(int nShape)
{
    switch(nShape)
   {
     case square:
     pt1.spX = 75;
     pt1.spY = 375;
     pt2.spX = 75;
     pt2.spY = 345;
     pt3.spX = 125;
     pt3.spY = 300;
     pt4.spX = 225; ///There is some kind of error in your///
     pt4.spY = 330; ///Original Drawcar function.///
     pt5.spX = 275;
     pt5.spY = 345;
     pt6.spX = 300;
     pt6.spY = 350;
     break;

    ....
   }

    return true;
}

void drawShape(int shpNum, int nColor)
{
    setcolor(nColor);
    switch(shpNum) 
   {
      case square://4 sided object
      SetPoints(4, square);
      L1={pt1,pt2}; L2={pt2,pt3}; L3={pt3,pt4}; L4={pt4,pt1}; 
        line(L1);
        line(L2);
        line(L3);
        line(L4);
      break;
      case 1:
        line();
        line();
        line();
        line();
      break;
   }
}

Then you could put other variables or static const type data in it as if needed.
Then next a Graphics function:

void DrawCar(spCar car, int nColor, int shpNum)
{
    setcolor(nColor);
    pieslice(100,400,40,10,25);
    arc((car.spX, car.spY = 75),90,190,30);//not sure of your arc function type//
    circle(100,400,25);
    drawShape(shpNum,nColor);

}

Rewrite your move function:

void move_sp(int a, spCar car, int shpNum)
{
    for(int i = 0; i < = 20; i++)
    {
       car.spX += a;
       car.spY +=a;
       DrawCar(car, setcolor(15), shpNum);
    }
}

then you can do your 'main' function:

int main()
{
    int g=DETECT,m; spCar Car; int Shape; int Color;  
    //to do set Color to a number that works, and decide on a shape(square for the example)//
    //and set the initial point 'Car'.     
    initgraph(&g,&m,"c:\\turboc3\\bgi");
    DrawCar(car, Color, Shape);
    move_sp(1, car, Shape);
    getch();
    closegraph();
    return 0;
}

Or something like that...