When we say the app is built for Android 4.4, it means that all the Android versions from 4.4 and above are supported, not just the 4.4 version.
A package name is a unique identifier for a specific set of files and code. It's usually used to differentiate between different apps on the Play Store! Make sure to create your projects with the latest up to date SDK. Currently, in 2020, that's Android Q or R.
This course was originally created in 2019. The content and student materials were reviewed and updated in October 2020.
With Android Studio installed and you registered as an Android developer, you'll get started by creating your first project.