Difficulty Integrating File Upload and Variable Insertion in Spine Web App

I am trying to create a web app where it is possible to view/test animations made in Spine by uploading the files from the user’s device or accessing them from a cloud folder and then share it with other people.

I am getting frustrated trying to figure out how to handle file uploads, and also how to insert the uploaded filename into the Spine JSON field. Currently, it doesn’t accept variables.

Can someone help please? Is it something doable using GDevelop at current stage?