This is the most basic lighting setup in Corona. You need to use shadow catcher material for the ground, set its projection mode to screen and plug solid white Corona color node to its backplate slot. Place Corona tonemap control node between Corona color and shadow catcher and uncheck all 3 its checkboxes if you want the white background always stay the same colour. Lastly plug the same tonemap control node as direct visibility override and you will have seamless transition from the floor to the background. Some terminology might be slightly different between 3ds max and C4D, but i think you should be able to figure out where to plug what.