Minimize your intake of lactose. Aside from foods containing high amounts of lactose such as dairy products, you should still be able consume a healthy, nutritious and balanced diet. Replacing your calcium and vitamin D intake from dairy foods can be substituted with lactose free alternatives such as lactose-free milk, soy milk, almond milk, and more.
A few of the many other lactose-free foods you can eat include
Meat, fish and poultry
Tofu
Peanut butter, nuts, seeds
Fresh fruit and vegetables