Thanks for replies. Sorry for misleading title with blizzard entertainment.
Decided to try ArseNic suggestion and simply made one snowflake appear on the screen. Once that worked I set up a loop with rand inside to generate x,y coordinates. This actually worked and produced a pretty good pattern. Was great full my skills taught me to problem solve.

Code:
 int x=10;
    int y = 10;
    int z =0;
    
   while (z< 700)
   {
    
    // draw snowflake at random positisons on screen
    hDC = GetDC(hWindow);
    DrawIcon(hDC, rand() % x, rand() % y, (HICON)(WORD)GetClassLong(hWindow, GCL_HICON));
    ReleaseDC(hWindow, hDC);
    x=x+ rand() % 300;
    y=y+ rand() % 300;
    z++;
That's it. Not sure if it's very optimised but works!
Thanks CornedBee for suggestion. Tried altering original with that code but it halted with GetClassLongPtr , GCLP underfined.