My son 14 years is a case of cerebral palsy advise treatment or medicine to make life comfortable?

Depends. Depends a lot on the kind of CP he has. Functional level will dictate orthopedic treatment, and many of the physiatry treatments (braces, wheelchairs etc). In a non- ambulatory patient, a good wheelchair is of utmost importance because they spend most of their time there. Ambulatory assistance may be more important in some less involved children. Surgery or gait aids may help.
Question too vague. Cerebral palsy can be so mild it is unrecognized or so involved the patient cannot function. To get the most from this site you need to provide basic background info about a problem and ask a specific question. If you will start over and focus on specific issues in the patient, we can likely help.There are books dedicated to this issue. Without more data, a specific recommendation is impossible.
Depends. It depends on how severe your child's symptoms are.In general physical, ocupational therapy could improve quality of life.Ancillary epuipment such as crutches, wheelchairs etx are rather useful.There are medications to assist with issues like drooling, behavioral intervention, skills training, counselling and above understanding and not placing a handicap on your child.Treat him respect/love.