If you want to access data in a file such as ggg.txt, then you need to open that file and read from it. This has nothing to do with Code::Blocks, and we won't teach you how to do that, since it's basics of programming, not Code::Blocks.
You need to learn how to use either the C++ iostream functions or the C stdio functions (which I personally perceive easier). Searching the internet for either of those terms will lead you to the documentation.
