How to use environment variables in a Code App (beyond data sources)?

[VictorKdy]

I’m trying to understand how to use environment variables in a Code App.

The official documentation only covers usage for data sources:
Use environment variables in code apps

However, it’s unclear how to work with string environment variables.

Questions:

How can string environment variables be accessed and used in a Code App?
Should I add environment variable tables as data sources (similar to Canvas Apps)?
Or is there a recommended / better approach?
Expected outcome:
Clear guidance or best practices for handling non–data source environment variables (e.g., strings) in Code Apps.