Need documentation

There should be documentation for explaining the server side code, as well as the folder structure. Even though it is inherited from create-react-app, some kind of documentation should be present.
**Steps to Reproduce**
NA
I would like to work on this.

Start by reviewing the repository's server-side code and folder structure, then compare the inherited create-react-app organization with what this project adds. Documentation is done when newcomers can understand the server-side code and navigate the folder structure without relying on undocumented conventions.

Written by the indexing model from the issue text.