How to fix mental problem?

Depends!: There are many, many types of "mental problems." If you are struggling, first see you primary care doctor and get a check up to be sure there is nothing physically wrong, as that can cause symptoms like depression and anxiety. Also, stop using drugs and alcohol as these cause many mental problems. Your doctor can then tell you the best professional to see to address any problems that remain.

Agree with Dr. R.: Counter-intuitive as it may seem, exercise may help. Start with low intensity exercise such as walking and gradually increase the intensity as tolerated. Have a healthy diet, exercise, drink plenty of water, have safe sex, and get HPV vaccine. Wish you good health! Nutrition: http://www.choosemyplate.gov/.