Using environment variables is fundamental in a project. This is how you tell your app if you are running in
locally for example. This is where you also store more sensible information like
SECRET_KEY or API credentials. Storing those directly in your web app code can be easy at first, but it is not safe when you will push your code in production, so taking good habits from the beginning is a good idea.
Before jumping in the topic of configuring environment variables, I will first make you set up and deploy a basic app.