Google Scripts code for forwarding SMS to Google Sheets – from https://medium.com/46-thoughts/receive-sms-into-google-spreadsheet-435b51393493

Code.gs

function doPost(e) {
  // Open the requested SpreadSheet and Sheet:
  var prop = PropertiesService.getScriptProperties();
  var spreadSheet = SpreadsheetApp.openById(prop.getProperty('SpreadSheetID'));
  var sheet = spreadSheet.getSheets()[0];
  
  // Append the data to the sheet on a new row:
  sheet.appendRow([new Date(), e.parameter['from'], e.parameter['message']]);
  
  // Return a empty text string to 46elks
  return ContentService.createTextOutput("");
}