HasibPrince

val filename = "myFile.txt"
val content = "Hello, World!"
        
val documentsDir = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOCUMENTS)
val file = File(documentsDir, filename)

file.outputStream().use { outputStream ->
    outputStream.write(content.toByteArray())
}

HasibPrince

val contentResolver = this.contentResolver
val contentValues = ContentValues().apply {
    put(MediaStore.MediaColumns.DISPLAY_NAME, "applounge")
    put(MediaStore.MediaColumns.MIME_TYPE, "text/plain")
    put(MediaStore.MediaColumns.RELATIVE_PATH, Environment.DIRECTORY_DOCUMENTS)
}

val uri = contentResolver.insert(MediaStore.Files.getContentUri("external"), contentValues)
uri?.let {
    contentResolver.openOutputStream(it)?.use { outputStream ->