Google App Script redirection page parameters

/*
This block detects if there scriptURL includes an especific parameter, if it does it will validate that the code exists in a Google Sheet, if exists, the user will be redirected to a especific page, of the parameter is not valid then it will be redirected to the error page.
*/

var spreadsheetID = 'your-spreadsheet-id';
var spreadsheet  = SpreadsheetApp.openById(spreadsheetID);

function doGet(e) {
  Logger.log("Received parameters: " + JSON.stringify(e.parameter));

  var userId = e.parameter.userId || "";

if (userId) {
    Logger.log("Found userId parameter: " + userId + " searching if exists in the spreadsheet");

    var sheet = spreadsheet.getSheetByName("your-sheet-name");
    var data = sheet.getDataRange().getDisplayValues();
    var found = false;


    for (var i = 0; i < data.length; i++) {

       //data[i][0] is the column where the userId is saved
      if (data[i][0] === String(userId)) {

        //If the userId is found, get the user name
        var userName = data[i][1];

        //If the userId was found in the spreadsheet

    if (found) {
       Logger.log("The user ID " + userId + "was found, redirecting to the user page");
      var template = HtmlService.createTemplateFromFile('userInterface');
      template.userName = userName;
      template.userId = userId;

      return template.evaluate()
        .addMetaTag('viewport', 'width=device-width, initial-scale=1')
        .setXFrameOptionsMode(HtmlService.XFrameOptionsMode.ALLOWALL);

    }  else {
    Logger.log("The user ID " + userId + "was not found, redirecting to error page");

    return HtmlService.createTemplateFromFile('errorPage').evaluate()
      .addMetaTag('viewport', 'width=device-width, initial-scale=1')
      .setXFrameOptionsMode(HtmlService.XFrameOptionsMode.ALLOWALL);
  }
}