OpenGL, Getting keyboard input ( any key pressed )

Question

Hi, I'm learning OpenGL.
the thing I know about getting input is:
if (glfwGetKey(window, GLFW_KEY_ENTER) == GLFW_PRESS)
doSomething();

I wanted to know is there any ways to see if ANY key is pressed?
like: std::cout << "You pressed a KEY !";

I want it for my first project in OpenGL.
it's my code: https://goo.gl/GvHQX7 ( line 45 & 46) ( you need some libraries to run it )
I wanted to print the RGB value when a key is pressed and I didn't found the way so
I Rapidly do system("cls") and print the RGB but I don't want it in this way

Answer 1

Thanks <3