I have moved your thread to a actual C&C forum.
Fill lighting is usually needed for bacl lit subjects so they are correctly exposed. In a scene like this one, even the pop flash on the camera will work well as fill light if it is used in manual mode, set to less than full power. one-quater powe is usually a good starting point at this distance.
Most full body shots of people that are not sitting on the ground, work better when the camera is turned to the portrait orientation.