Thank you for the question.
I'm sorry to hear about your concerns regarding the breasts' appearance. Based on your description of weight loss and the effects it has had on your breasts, There are a variety of different ways to improve the position and size of your breasts. Exactly the procedure that is performed depends on your goals in regards to size, shape, superior pole volume etc.
Breast lifting procedures are associated with scars on the breasts; exactly where these scars will be located will depend on the patient's physical examination and specific procedure performed. Most patients undergoing this procedure will accept scarring as long as their overall goals in regards to size, shape, contour and symmetry are met.
In person consultation with well experienced board-certified plastic surgeons will be the best place to start. As you do your “homework” you will learn about the potential risks/complications. Also consider issues such as timing of the surgery in relation to your life circumstances ( such as relationships and/or pregnancies).
Make sure you do your due diligence and see lots of examples of the plastic surgeons' work.