How do you make an Arduino count down timer?
For (int i = 0; i &lt; 12; I++) {
      Int pixelNum1 = 1;
      strip.setPixelColor( pixelNum1, 244, 0, 0);
      strip.show();
      delay (27);
      pixelNum1 ++;
    }


Assuming you fix the upper-case lower-case issues here first, you've still got a scope issue.  Since pixelNum1 is defined inside the for loop, it will go out of scope at the end of the for loop.  So it will be 1 on every iteration and it won't increment like you seem to think it will. 

Why don't you just get rid of it altogether and use i+1 instead?