Adaptation to my data for an example

Hello guys,
I want to adapt the example of a “Hierarchical edge bundling” for my data which are similar to the existing ones. I have got rudimentary skills in coding but they are limited. I also got some experience with jupyter notebook which are similar to the notebook I saw here. But I am honest I can’t identfiy where the database is and where I can manipulate it. Currently I try to edit the flare.json in my local http server to effect changes but there are none. What will be the “official way” or “best way” to adapt such an example for individual modifications? I there are possibility to generate a new flare.json?
Sorry for the total beginner question. Thanks for help!

Maybe this example using Observable Framework is easier to adapt than a notebook; basically the same code, but the data file is handled a bit differently. If you replace the file with your data (and provided it has the same shape), it should work.

https://observablehq.observablehq.cloud/pangea/d3/hierarchical-edge-bundling

Let me know if you have questions.