Often when a dog decides to stop eating it means that they are going to die. Eleven is an old dog when it is mixed with wolf. Since the dog has been seen by a doctor I would suspect there is not much to be done for this dog save to make him comfortable (manage his pain).
So sorry to hear of his troubles.
In case of Puking Foam , Her digestive system isn’t good. But blood is coming?!?? She got a stomach cancer. Keep calm and visit a vet as soon as possible if you want to save her.