Using node.js custom function to send form data to external api

Using node.js custom function to send form data to external api

I have a form I am working on that once it's filled out, it will send it to a third party app through an api.  I am using a custom function with node.js.  Where I am "stuck" is getting the fields from the form into the custom script. I tried to call them via the field name but had no luck in that. My guess is I will need to "get" the field names on the form in a separate api call and then refer to them in the second api call to the third party app. What I am finding here is always for the CRM and not the form itself. Can someone guide me in the right direction? I appreciate it.