Why does the build.gradle file appear in Android studio like this ...?

Why does the build.gradle file appear in Android studio like this ...? SDK Dependency Sync Can't Be Synced When Connecting Firebase (In an App Building Using Java)

// Top-level build file where you can add configuration options common to all sub-projects/modules.
plugins {
    id 'com.android.application' version '7.1.0' apply false
    id 'com.android.library' version '7.1.0' apply false
}



task clean(type: Delete) {
    delete rootProject.buildDir
}