I just turned 16, male, 170cm, 170 kg, puffy. . The beard is just a little hairy and the Adam's apple is a little long, but the voice hasn't changed much.
Eating less and exercising more is the healthiest way to lose weight. I was fat when I was in the second grade, but I didn't grow up. Later, I went swimming, didn't eat dinner, and then came back to eat something. I lost more than a month, and then I grew up. You can also try, but you may rebound if you don't swim, so you should always exercise more.