<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

        ContentValues values = new ContentValues();
 
        values.put(MediaStore.MediaColumns.DISPLAY_NAME, "menuCategory");       //file name
        values.put(MediaStore.MediaColumns.MIME_TYPE, "text/plain");        //file extension, will automatically add to file
        values.put(MediaStore.MediaColumns.RELATIVE_PATH, Environment.DIRECTORY_DOCUMENTS + "/Test/");     
        Uri uri = getContentResolver().insert(MediaStore.Files.getContentUri("external"), values);
 
        OutputStream outputStream;
        try {
            outputStream = getContentResolver().openOutputStream(uri);
            outputStream.write("This is menu category data.".getBytes());
            outputStream.close();
            Toast.makeText(this, "File created successfully", Toast.LENGTH_SHORT).show();
 
        } catch (FileNotFoundException e) {
            Toast.makeText(this, "Fail to create file", Toast.LENGTH_SHORT).show();
        } catch (IOException e) {
            Toast.makeText(this, "Fail to create file", Toast.LENGTH_SHORT).show();
        }