How to eliminate the back in portrait photography? Does the back of the character need polishing?

You took this with an overhead flash! Two lights hit both sides, then people stay away from the background and the shadow disappears! Pay attention to adjust the index of two lamps to follow the principle that there is only one sun, that is, one light intensity is weaker than the other, which is more stereoscopic! If you like the clean picture, you can also add lights! I hope it will help your problem! Please adopt!