just want to ask is there any tutorial on how to structure Android Studio coding? i'm new in Android Studio, looking for some best practice to manage our code. Thanks so much.
Concerning the impact of the gradle build tool on the organisation of your project, you could use this link: Gradle Plugin User Guide. It is not strictly speaking a tutorial but it's easy to read.
Concerning the overall organisation of an Android studio project, and in particular the use of one or several modules in your project, maybe Android studio: new project vs new module can help you.