how to change background and font color in c++ program

Answer 1

If you mean the colours of the command prompt, you'll want to look in to the NCurses library, I'm not aware that this is possible through code alone without such a library.

Answer 2

use a compiler every thing has different colors in it

Answer 3

If you're making OS specific code you can use system command calls it's simple, easy and fast but waaaaaaay too slow in larger programs
NCurses is still the best bet, but system calls are easier for short stuff