As a fitness white 178 75kg, how to reduce fat?

178,75 75kg is not very fat, but since you mentioned reducing fat, it must be that with the growth of age, sitting in the office for a long time leads to fat on your stomach. Just like you, losing weight is actually easier. Give you some advice;

As a fitness girl, first of all, you should form the habit of exercising. I suggest you start with 2-3 times a week. At first, the movement can be simplified. For example, when the air is fine for 2-4 days a week, go outdoors more (brisk walking, speed 1 1 min, 1 km) or if you have a certain foundation, start with jogging and brisk walking every time.

After getting into exercise habits, you should control your diet properly. The "control" here is not to control food intake, but to control calories. Stay away from those fried foods and drink less drinks.

These things have been done. I suggest you go to the gym and ask a personal trainer to make further systematic contact to lay a good physical foundation for the future.