How to transfer patient from one site to other using API/Packages?

We have patient data coming from external sources. This data needs to be populated into Oracle clinical by calling appropriate API or Packages. The data includes site information for that patient. To enroll a patient there is API enrollpatient. My questions:

How do we assign the site to the patient from back end?

How do we transfer the patient from one site to another site from backend. 

I need your help in  knowing the API or the package which will allow me to assign site to patient or transfer patient from one site to another site.

~Regards,