Accessing the Google Sheets API

sheets.php

<?php

     // Insert into the sheet
     $options = array('valueInputOption' => 'RAW');
     $values = [
         ["$email","$first_name","$last_name","$zip_code"]
     ];
     $body   = new Google_Service_Sheets_ValueRange(['values' => $values]);
     $result = $service->spreadsheets_values->append(SHEET_ID, 'A1:D', $body, $options);