Adobe sign workflow

For some API calls to call the workflow,I need the transient document id. According to my understanding do I only get a transient document ID if I upload a pdf but not if I'm creating an agreement from a document library template. Can I get transientID from the shared document library.

For example. I want to pre-fill custom input fields in my agreement (https://helpx.adobe.com/sign/kb/send-an-agreement-with-merge-fields-using-api-adobe-sign.html) I have to use the transientDocumentID.

And also, How Can I find out workflow ID from my personal account? Is there  a way to link my workflow with one of the applications in my personal account?