Hi my name is Ahmed am British citizen living in Somalia.

Ahmed, it’s possible for you to get that from Djibouti.
You should first prepare the relevant documents including your passport and copy of its data page, the application form affixed with a passport-style photo, your valid visa for Djibouti, and the invitation letter, as well as other documents the consular officers consider necessary. Next, go to the embassy of China to submit the application.