Drawing a sphere using for loop ( i want to draw a sphere instead of circle please help)

}
void drawCircle(double x, double y, double r) {
	
	glColor3f(nodeBGClolor.r, nodeBGClolor.g, nodeBGClolor.b);
	int iterations = 500;
	glBegin(GL_POLYGON);
	
	
	for (int i = 0; i < iterations; i++) {
		double currX = r * cos(2 * PI * (i / (iterations * 1.0)));
		double currY = r * sin(2 * PI * (i / (iterations * 1.0)));
		glVertex2f(x + currX, y + currY);
		
		
	}
	glEnd();
}