Why are my 3d shapes in OpenGL/GLFW C++ missing faces

Why are my 3d shapes in OpenGL/GLFW C++ missing faces

So when i make a 3d triangle it just misses faces as shown below (with
quad) any shape i try misses faces and you can just see straight through,
(mind this is my first time using both OpenGL and GLFW)
The shape code is from a tutorial as ive tryed many shape codes to see if
that was the issue and it seems it is not.

#include <glfw3.h>
#include <stdio.h>
#include <iostream>
using namespace std;
/* Begin Void prototyping */
void error_callback(int error, const char* description);
static void key_callback(GLFWwindow* window, int key, int scancode, int
action, int mods);
int main(void)
{
GLFWwindow* window;
/* Initializes error call-backs */
glfwSetErrorCallback(error_callback);
/* Initialize the library */
if (!glfwInit())
return -1;
/* Create a windowed mode window and its OpenGL context */
window = glfwCreateWindow(640, 480, "Hello World", NULL, NULL); //
fullscreen glfwGetPrimaryMonitor() (first NULL)
if (!window)
{
glfwTerminate();
return -1;
}
/* Makes OpenGL context current */
glfwMakeContextCurrent(window);
/* Make the window's context current */
glfwMakeContextCurrent(window);
/* Receives input events */
glfwSetKeyCallback(window, key_callback);
/* Loop until the user closes the window */
while (!glfwWindowShouldClose(window))
{
/* Render here */
float ratio;
int width, height;
glfwGetFramebufferSize(window, &width, &height);
ratio = width / (float) height;
glViewport(0, 0, width, height);
glClear(GL_COLOR_BUFFER_BIT);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(-ratio, ratio, -1.f, 1.f, 1.f, -1.f);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glRotatef((float) glfwGetTime() * 50.f, 0.f, 0.f, 1.f);
glBegin(GL_TRIANGLES); // Start Drawing A
Triangle
glColor3f(1.0f,0.0f,0.0f); // Red
glVertex3f( 0.0f, 1.0f, 0.0f); // Top Of Triangle
(Front)
glColor3f(0.0f,1.0f,0.0f); // Green
glVertex3f(-1.0f,-1.0f, 1.0f); // Left Of
Triangle (Front)
glColor3f(0.0f,0.0f,1.0f); // Blue
glVertex3f( 1.0f,-1.0f, 1.0f); // Right Of
Triangle (Front)
glColor3f(1.0f,0.0f,0.0f); // Red
glVertex3f( 0.0f, 1.0f, 0.0f); // Top Of Triangle
(Right)
glColor3f(0.0f,0.0f,1.0f); // Blue
glVertex3f( 1.0f,-1.0f, 1.0f); // Left Of
Triangle (Right)
glColor3f(0.0f,1.0f,0.0f); // Green
glVertex3f( 1.0f,-1.0f, -1.0f); // Right Of
Triangle (Right)
glColor3f(1.0f,0.0f,0.0f); // Red
glVertex3f( 0.0f, 1.0f, 0.0f); // Top Of Triangle
(Back)
glColor3f(0.0f,1.0f,0.0f); // Green
glVertex3f( 1.0f,-1.0f, -1.0f); // Left Of
Triangle (Back)
glColor3f(0.0f,0.0f,1.0f); // Blue
glVertex3f(-1.0f,-1.0f, -1.0f); // Right Of
Triangle (Back)
glColor3f(1.0f,0.0f,0.0f); // Red
glVertex3f( 0.0f, 1.0f, 0.0f); // Top Of Triangle
(Left)
glColor3f(0.0f,0.0f,1.0f); // Blue
glVertex3f(-1.0f,-1.0f,-1.0f); // Left Of
Triangle (Left)
glColor3f(0.0f,1.0f,0.0f); // Green
glVertex3f(-1.0f,-1.0f, 1.0f); // Right Of
Triangle (Left)
glEnd(); // Done Drawing
The Pyramid
/* Swap front and back buffers */
glfwSwapBuffers(window);
/* Poll for and process events */
glfwPollEvents();
}
glfwDestroyWindow(window);
glfwTerminate();
return 0;
}
/*
Calls back the program if a GLFW function fail and logs it
*/
void error_callback(int error, const char* description)
{
fputs(description, stderr);
}
/* Gives keys events */
static void key_callback(GLFWwindow* window, int key, int scancode, int
action, int mods)
{
switch(key)
{
case GLFW_KEY_ESCAPE:
glfwSetWindowShouldClose(window, GL_TRUE);
break;
case GLFW_KEY_W:
cout << "W works!!!" << endl;
break;
case GLFW_KEY_A:
cout << "A works!!!" << endl;
break;
case GLFW_KEY_S:
cout << "S works!!!" << endl;
break;
case GLFW_KEY_D:
cout << "D works!!!" << endl;
break;
}
}
Ive been trying to fix it for hours i just dont know what too do now
Im using OpenGL 3+ with GLFW and C++