Do i have to lose weight in order to tone my body?

If obese, yes: Obesity is caused by a genetic mechanism in the hypothalamus (a brain center) that is normally silent. High calorie malnutrition, particularly sweets and sweeteners, turn it on. Thus the brain takes part in body fitness.

Toning. : It depends what you mean by tone. One can improve muscular strength and endurance without losing weight, and thus improve muscle tone. However, it will not be as evident to an observer as toning with weight loss.