How to retrieve File produced by Assistant API using cURL and save it?

Hello Community , I can not figure out as of yet how to download a file using the cURL retrieve Method presented here:

Here are some screenshots of what I tried using Postman:

My original intention is to retrieve and Download the File using FileMaker:

The URL to be called and the Payload can be seen in the following Screenshot:

I would be very thankful if someone could give me a tip on how to deal with it.

Thanks in advance