I don’t know why, but a lot of people in the C++ class I had to take at school had the same misconception you seem to have.
Doing this…
#include <glut.h>
Is not adding the library.
.h files are what are called header files, not libraries. That means that they contain prototypes for functions, etc. They do not contain the object code for those functions. That object code is what is contained in the actual library. The actual library has an extension like .lib or .a or .so etc. depending on the compiler.
To add a library, you need to tell the linker which library to link in to the final binary. I’m not sure exactly how this is done with CodeWarrior, but somone else may be able to tell you how. You should look for some project setting that lets you specify libraries/object modules, etc.