For large purchases such as carpets, ask the merchant for a receipt, so that you have proof of the value for customs purposes later. Urdu is spoken throughout Pakistan. Many people speak some English. Most people speak other regional language, such as Punjabi or Pushto. You should be able to manage in English.
Food is generally spicy.
Yogurt provides a good balance. All fresh fruit and vegetables should be peeled. Oranges are in season in November. The mangoes have just finished at conference time. Use it even for brushing teeth.