You may keep your Islam a secret from your parents and family if you are quite sure they will make your life very difficult. You may pray through gestures or by leaving the house. If you are pressured to eat while fasting, you can eat to the extent that you have to and it will not break your fast. If you are strongly pressured or forced to eat pork, you may do that to the extent it is needed.
Shaykh Mustafa Umar