Using the API to write/read data to a Custom field collection

Using the API to write/read data to a Custom field collection

We when create our tickets, we are selecting from a dropdown list of values.

We would like to using the API add more values to the list so they can be selected.

For example this is the ticket data. from https://desk.zoho.com/api/v1/tickets/394 .....
       "cf": {
"cf_company": "Zydus"
      }


The user selected "zydus from a dropdown"; we would like to read all the available "cf_company" values in an API call and add more to the list via a post.

We basically want to send information to Zoho, and have that information be available to be selectable on the ticket.