You should have the Visa Notification letter from relevant authorities in China, namely, Ministries and Commissions of the State Council, the Government of all Provinces, Autonomous Regions, and Municipalities directly under the Central Government, and Foreign Affairs Offices and Bureaus of Economy and Commerce thereunder, and departments and units recognized by the Department of Consular Affairs of the Ministry of Foreign Affairs of the People's Republic of China. (The inviter know how to get the visa notification letter)

The invitation letter from the invitor with the stamp of the company, origanizor, etc

if you have them, then you can prepare your passport, fill one visa application form attached with one passport photo, go to the Chinese embassy in Kabul to apply for China Business Visa.