API to fetch related module data to create a WO

We are trying to build a 2 way integration between Facilio and Corrigo for Workorder Module .
Inorder to achieve the same , we need to maintain a mapping of certain attributes in Facilio ( such as customer , property etc) .
Where can we find the API's to fetch the related data that has to be maintained or mapped to create a Work Order in Corrigo (such as the following):
Customer
Category
Subcategory
Task
Priority
Property
Asset