I had a cancer in my left kidney when i was a kid , what is the chance that a cancer could happen to me back in the future ?

Not the same kind: Kidney cancer that occurs in children does not occur in adults. In general people who have had cancer are at greater risk for a second cancer. It would be prudent to have a primary care doctor who may evaluate your health and advise you for your specific health issues. For good health - Have a diet rich in fresh vegetables, fruits, whole grains, low fat milk and milk products, nuts, beans, legumes, lentils and small amounts of lean meats. Avoid saturated fats. Exercise at least 150 minutes/week and increase the intensity of exercise gradually. Do not use tobacco, alcohol, weed or street drugs in any form. Practice safe sex.