You have to take action and make a life for yourself. Do stuff.
A happy life is about trial and error, or trial and success. The main thing is to have activity planned for every day. School, part-time job, exercise, friends, and so on.
There are no magic pills to solve the problem of inactivity. Medication can be successful for people with major mental illness or deep depressions, but other than that, the best thing for people is to lead an active life, according to several recent studies.
Good Luck to you in the future.
