⤷ Open Printer Properties window

Use OpenPrinter procedure for getting printer handle and PrinterProperties procedure for opening printer properties window.
Don't forget include WinSpool and Printers in uses chapter.

uses WinSpool, Printers;
... 
procedure TForm1.Button1Click(Sender: TObject);
var
  MyPrinter, MyDriver, MyPort: array[0..100] of Char;
  PrinterHandle, DevMode: THandle;
begin
  Printer.GetPrinter(MyPrinter, MyDriver, MyPort, DevMode);
  OpenPrinter(MyPrinter, PrinterHandle, nil);
  PrinterProperties(Form1.Handle, PrinterHandle);
end;
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