No, you cannot breastfeed after FTM top surgery. During FTM top surgery, the mammary glands and ducts responsible for milk production are removed. This means that you will no longer be able to produce milk. There may be a small amount of glandular tissue left behind, but this will not be enough to produce milk.
However, there are some transgender parents who have had breast/top surgery and still wish to breastfeed, or chestfeed (a term used by some transgender and non-binary parents), their infants. They may be able to do so by pumping breast milk before surgery and storing it for later use. They may also be able to use donor milk or formula.
If you are considering FTM top surgery and are concerned about breastfeeding, it is important to talk to your surgeon about your options. They can help you understand the risks and benefits of different approaches to breastfeeding after surgery.