Beginning flight training with a certified instructor has no upper age restrictions. A person pursuing their private pilots certificate must be at least 17 years old in order to receive the certification. Upon receiving your private pilot rating, you may continue to fly as long as you are able to pass the required medical examination to ensure your medical certificate is up to date and take the required biennial flight review.
Mandatory retirement age for commercial pilots has been raised from 60 to 65 when flying international flights. The complete details of this may be found in HR4343.