I am presently 80kg and 5feet 8 am i overweight? and i do i reduce my weight to 75 kg

Yes, overweight.: I'm not sure what the question is. In most people, excess weight is caused by overeating. There are exceptions. [hypothyroid, genetic factors, diabetes, e.g.] ]Reducing 5 kg would reduce various health risk factors. See a nutritionist for appropriate meal plan. Get regular moderate exercise. If little weight loss on good diet, get checked for these other factors.