I am sorry but I do not recommend steroids for weight gain. You are underweight for your height. If you do 'work out' with weights, you will gain weight. As you gain lean body muscle, you will gain weight because muscle weight more than fat. Suggest you eat 3 times a day with snacks between meals. Suggest drinking 2-3 times a day either nutrient dense drinks (in addition to eating your meals) such as ensure or make your own milkshakes or yogurt smoothies - milk, ice cream, and frozen fruit blended together, or yogurt, milk, and frozen fruit blended together for extra calories, protein and nutrients to help increase your weight.