Is there a way to change flat face?

Sure: There are several surgical options and approaches to "change a flat face" this can be done by means including but not limited to facial implants, bone grafting and skeletal repositioning. Once you are ready for a detailed discussion on the matter, contact your local oral and maxillofacial surgeon or plastic surgeon.

Surgery: Yes. There are a variety of surgical augmentation options. Best to get a few opinions from different specialists. Try oral & maxillofacial surgeons and/or facial plastic surgeons.