If your forehead is convex, don't think about flattening it, just think about how to weaken this shortcoming of yourself. Because it is impossible to ask you to cut bones, and the operation of cutting bones is only for cheeks. The skull is hard and the operation risk is relatively high. For the sake of life safety, I don't consider surgery, but only consider weakening my shortcomings in other ways.
You can make an air bangs that is very popular now. The air bangs are not as thick as the bangs. If you have acne on your forehead, you don't have to worry about stuffy acne.
Cover your forehead with air bangs, so that when others look at you, they will pay attention to your face, not your forehead. Except when you look at your forehead from the side, you will be fine. In this way, the face value is also online, and the short board of the forehead is also weakened.
Or split your hair so that you can cover the protruding parts of your forehead on both sides. If you only look at the front, you won't feel your forehead protruding. In this way, your whole popularity field has also become stronger, and the shortcomings of your forehead have also weakened.