Plz tell me on low protein diet person lose fat or muscles also doing calories deficit i know that low protein cause muscle loss what do you think ?

Balance is key: Protein is necessary for cellular repair especially if you are exercising. Healthy fats (omega-3) is also necessary for healthy tissues and is a good source of energy. Stay away from trans fats. Limit processed food intake, sugar-especially high fructose corn syrup which is hidden in many foods. If you are restricting your caloric intake you will indeed loose muscle and may store fat.