Just like Java classes you can create Interface in android studio. This article will help you create an interface under your package name. Please follow the below given steps to create a new Interface.
How to create an Interface in Android Studio
Step 1: Open your Android Studio and navigate to Android View
Step 2: Select and open App folder then Java > yourPackageNAme(com.example.myApplication).
Step 3: Right click on package name then New > Java Class.
Step 4: Android Studio will open a dialog box. Enter a name for your Interface. Change its type by selecting KIND options and select Interface from the drop down list. Then click on Ok.
Now you will have an Interface under your Package name.