Do you mean to apply for a visa to China in Gambia as a non-citizen there? If yes, you are required to provide following documents when submit your visa application to Chinese embassy:
1. Your passport valid for at least 6 months; 2. One recent passport photo; 3. An application form that you need to fill completely; 4. Hotel reservations and round trip air ticket to China; 5. your pass record or stay permit in Gambia. AND others may asked by visa officers.