Calories in, calories out.
Weight loss is rather simple: you need to use more calories on a rolling basis than you take in. So without dietary changes, you need to significantly increase aerobic activity: running, walking, etc. Or you could calorie restrict your diet.
But it’s best to do both.
The fat on your face is subcutaneous. It’s the padding the body places there to protect the structures underneath. Subcutaneous fat is also the last of the fat stores to be metabolized. So if you have significant amounts of visceral fat (in the abdomen and neck), there will likely be some improvement in the face; but it won’t significantly change until you reach a lean body fat percentage.