Breast far apart no cleavage and after weight loss loss of upper pole fullness.can gaining weight reverse this?any treatment age 23

None recommended: Trying to gain weight to get full breasts is a bad idea. You are likely to get fat without fuller breasts. If you must, you may consider getting a breast implant. I am not recommending it, jut informing you of the option. For good health - Have a diet rich in fresh vegetables, fruits, whole grains, milk and milk products, nuts, beans, legumes, lentils and small amounts of lean meats. Avoid saturated fats. Drink enough water daily, so that your urine is mostly colorless. Exercise at least 150 minutes/week and increase the intensity of exercise gradually. Do not use tobacco, alcohol, weed or street drugs in any form. Practice safe sex. Get HPV vaccine.