I doubt anyone will answer this question given the way it is phrased (of course I just have proving myself wrong:D)
What do you mean "using codes"?
I would have thought the 2 ways you could open a file were to use the Open item off the File menu or to put the file name on the command line when you run C++ Builder.
Of course if you actually mean what is the C/C++ code for opening a file that is a different question. There a re many ways 1 would be to use the function
fopen.
You can find help for this function
here. While you are there also read about fclose, fread and fwrite.