Reduce it to 45?

You are 175. 63 is normal ~ not fat

If you really want to lose weight, eat normally at noon in the morning, with more essence and less quantity.

Is to eat high nutrition, but less.

Don't eat at night, just drink water.

If possible ~ you run to school every day ~

Because you are a high school student, you may not have that much time to exercise.

Exercise at rest, too.

I was very thin in the third grade, and that's how I lost weight.

Moreover, there was a physical education exam at that time. At the end of the second class in the morning, the school organized running.

But not now ~ ~ I'm lazy .....