You need to submit your China visa application to Chinese embassy in Qatar. The requirements are your passport, one passport photo, an application form which you can find on the top of this page.

For a tourist applicant, in principle you shall evidence your financial capability of covering the travelling expenses in China, and when necessary, provide the air, train or ship tickets to the heading country/region after leaving China. If you come to China to visit relatives, you are required to provide invitation letters from their relatives in China.

how much should be financial capability