how can i get business M type while staying in china?

Torres, you can try to convert the student X type to business M type at the exit and entry administration of the local PSB within China. If it can be done, you don't need to leave China.
You should prepare the relevant documents including your passport and its copy, the application form, a passport-style photo, valid registration form of temporary residence, invitation letter from your business partner, and other required documents. Then, submit the application to the local PSB.