Public schools are free. First, the fees charged by public schools include not only tuition fees, but also insurance fees and school use fees. Exempting tuition fees does not mean exempting all fees. Second, only some schools are free of tuition, not all. Besides, the French economy has been bad in the past two years, and many schools have started to increase tuition fees. Third, if it is a French college enrollment program in China, basically you can't expect to be free of tuition. I'm here to make money, so it's good not to kill you. The general cost of a master's degree is around 1300 euro/year, but majors such as economy, trade and commerce will be more expensive.
French masters usually take two years, but their bachelor's degree is three years, so it adds up to five years. According to China's four-year capital, the master's degree is really only one year. However, some master's majors only need to study for one year according to different requirements.
A master's degree in psychology and a French diploma should be good. I know a man who has a French diploma and earns a lot of money by opening a clinic in China.