Dogs like to scratch themselves is normal

Is it normal for dogs to like to scratch themselves? It is not normal for dogs to like to scratch themselves, which means they may have a skin disease. The fungus in the air has infected the dog and caused the skin disease. When this is found, the breeder needs to take the dog to the doctor promptly for treatment. It may also be because the dog has fleas and the dog feels itchy so it keeps scratching itself. The breeder needs to bathe the dog and use in vitro deworming to get rid of the fleas on the dog. It may also be because the dog is suffering from mites, which are more serious and cannot be treated by bathing and in vitro deworming. The breeder needs to take the dog to the hospital for an injection to treat it.