Send active sheet as PDF to email listed in cell

below is a working version with a few useful parameters you may want to use.

UPDATED CODE

function sendSheetToPdfwithA1MailAdress(){ // this is the function to call
  var ss = SpreadsheetApp.getActiveSpreadsheet();
  var sh = ss.getSheets()[0]; // it will send sheet 0 wich is the first sheet in the spreadsheet.
  // if you change the number, change it also in the parameters below
  var shName = sh.getName()
  sendSpreadsheetToPdf(0, shName, sh.getRange('A1').getValue(),"test email with the adress in cell A1 ", "This is it !");
}
function sendSpreadsheetToPdf(sheetNumber, pdfName, email,subject, htmlbody) {
  var spreadsheet = SpreadsheetApp.getActiveSpreadsheet();
  var spreadsheetId = spreadsheet.getId()  
  var sheetId = sheetNumber ? spreadsheet.getSheets()[sheetNumber].getSheetId() : null;  
  var url_base = spreadsheet.getUrl().replace(/edit$/,'');

  var url_ext="export?exportFormat=pdf&format=pdf"   //export as pdf

      + (sheetId ? ('&gid=' + sheetId) : ('&id=' + spreadsheetId)) 
      // following parameters are optional...
      + '&size=A4'      // paper size
      + '&portrait=true'    // orientation, false for landscape
      + '&fitw=true'        // fit to width, false for actual size
      + '&sheetnames=true&printtitle=false&pagenumbers=true'  //hide optional headers and footers
      + '&gridlines=false'  // hide gridlines
      + '&fzr=false';       // do not repeat row headers (frozen rows) on each page

  var options = {
    headers: {
      'Authorization': 'Bearer ' +  ScriptApp.getOAuthToken(),
    }
  }

  var response = UrlFetchApp.fetch(url_base + url_ext, options);
  var blob = response.getBlob().setName(pdfName + '.pdf');
  if (email) {
    var mailOptions = {
      attachments:blob, htmlBody:htmlbody
    }
MailApp.sendEmail(
      email, 
      subject+" (" + pdfName +")", 
      "html content only", 
      mailOptions);

MailApp.sendEmail(
      Session.getActiveUser().getEmail(), 
      "FRWD "+subject+" (" + pdfName +")", 
      "html content only", 
      mailOptions);
  }
}