Weight loss = caloric deficit, the easiest way to achieve this is a combination of exercise and reducing calories, go to IIFYM.COM and calculate your TDEE then eat 500-1000 less cals than this to lose 1-2 lbs per week. Some people do 'intermittent fasting' where they eat all their calories in a small time window like 6 hours and that's fine, but fasting as in never eating anything for days/weeks on end is completely stupid and unhealthy and will just lead to malnutrition and an eating disorder.