these are the header files i need to work on it: BIOS.H STDLIB.H STDIO.H

Considering that this is the Everything Unix forum, there is a very good chance that you already have the gcc compiler already installed on your computer. Type "man gcc" into a terminal window. If you're not using unix, then this is probably not the place to ask this question.

Plus, *nix is case sensitive, the compiler will never find BIOS.H STDLIB.H or STDIO.H, but will have no trouble with bios.h stdlib.h or stdio.h