i am British passport holder in dubai for a month during my stay in Dubai can aply Chinese visa

Nirmala, you can apply for it in Dubai. You should first prepare the relevant documents containing your passport and its photocopy, the application form, a passport-sized color photo, valid entry permit to Dubai, hotel reservation and flight itinerary; or if your friend has residence permit in PRC, he/she can write an invitation to you, and in this way, no hotel reservation and flight itinerary are needed.
Afterwards, submit the application to the embassy of PRC to apply for the L type to visit PRC.