For GERD, first of all avoid eating any junk food or oily,spicy food.Take a healthy,balanced and nutritious diet consisting more of fruits,salads,soups and raw vegetables(after proper washing).Also increase the protein content in your diet instead of carbohydrates and fats.An advice from a dietician will be helpful. Try raising the head of your bed about four inches with blocks. It also might help to avoid eating or drinking for two hours before you lie down. To help control the stomach acid, one should not drink alcohol or drinks with caffeine in them, or eat chocolate or spicy or greasy foods .
Also start moderate exercises on a daily basis.Start with walking and then you can shift to jogging and cardios.
For kidney stones, drink plenty of fluids and water. There are many types of kidney stones and depending on that, avoid high protein diet and diet rich in calcium and oxalates. Avoid vegetables and fruits containing seeds such as tomatoes, lady’s finger, brinjal, capsicum, watermelon, guava etc.
I sincerely hope that helps. Take care.