Bubble to Create Instagram Post (Via Make.com)

Hi All

I am completely new to bubble and building websites but I am trying to work out how to have bubble send a image file to make.com/integromat so it can post on a social media page. I want to upload an image, write a description and post.

The big issue I am having is the URL is not compatible when instagram tries to create a post. Does anyone know how I can do this? open to changing process just trying to find the best way to do this.