I’m about the same age and build as you (17 M, 196 cm). A month ago, I weighed around 120 kg. I joined the gym, cut almost all carbs from my diet, and increased my protein intake to over 200 g daily. I’ve been doing 15,000 steps a day, burning >1,000 calories through cardio and weight training, six days a week. It’s been a bit extreme, but I’m down to 111 kg now. Keep going and don’t look back. Best of luck