I would like to know how to lose 12 kg and 5 inches off the waist within 6 weeks? (safely)

Get started: 24-27 pounds in 6 weeks. that is 4 pounds a week. and you want to do this safely. If you want to do it safely, I suggest reevaluating your goals. 2 pounds a week is more realistic. To lose inches off your waist, you would have to lose fat and build muscle- so strength training along with aerobic exercise and good eating habits are essential. Try eating less and moving more.