What is the best and fastest way to lose quick weight?

No magic bullet. Most studies show that even if you succeed in rapidly losing weight through drastic dieting, few people maintain the weight loss without truly changing their eating habits to a healthier approach, and also incorporating increased activity. Overall, the only true way to succeed in weight loss (without surgery) is to decrease the calories you eat and increase the calories you burn up each day.
Eat fewer calories. Helpful weight loss diets include natural foods that take time to chew but contain few calories. Examples include carrots, celery, and iceberg lettuce (without salad dressing). When shopping for fruits, buy small ones no bigger than a tennis ball, because fruits contain natural sugar. Drinks without calories include water and green tea. A calorie is a calorie, regardless of where it comes from.