Hi. I arrived in beijing, china three days ago, and im planning to apply by myself to have residency

You can apply for a residence permit yourself, but you should submit all the necessary documents such as your passport, accommodation registration printout from the police, physical examination results and the emplyment contract from your employer. I'm afraid you can't use your present work visa to work for other employers unless under the permit of your present employer.

You still have to do another physical exam at an authorised medical center in China again for the residence permit application.