I have written my code in c++2012 in windows 7 with win32 and console for seeing the result of my program. Because my program must be competitive by passing the time (time is being measured for every step of solution), I think that in console some extra time is consumed to write the output data.
My question is that: Is my proposition true and if true how do I change my c++ project type ?
I think your question is does it take more time to write things to the screen when you run your program, and the answer is YES. You can test this by simply not writing the output to the screen and see how fast it finishes.
If you want to avoid that, write the output to a file.
I doubt that you really need to worry about it. The people who write contests are aware of the constraints on you, including what takes time in various solution patterns. I/O isn't usually a significant factor -- your algorithm is more likely to need help.