documents and type of visa if I want to attending train courses in China.

You may need to apply for a F type for attending the courses.

The needed documents are an invitation letter of Duly Authorized Unit, an invitation letter from your courses, introduction from your university, bank statement with at least 6 months' deposit records if it is your first application, your application form with a recent taken photo and your valid passport.

Thanks a lot. Please can I make appointment for application in the china embassy in lagos next week because I heard some embassies are closed due to ebola crisis

The appointment can be made in Lagos, so please do not worry. You need to hand in your documents when you make the appointment.