sendEmails.gs

//https://gist.github.com/chemiadel/f1314bf8403eda071ca10c584947d1e7

//Sheet Name
SHEET_NAME="Emails"

function sendEmails() {
  //Assign Spreadsheet, Sheet to object variables
  var ss=SpreadsheetApp.getActiveSpreadsheet();
  var sheet=ss.getSheetByName(SHEET_NAME);
  
  //Get data into 2D Array
  var values=sheet.getRange('A2:E'+sheet.getLastRow()).getValues();
  
  for(var i in values){
    //Verify if email is Ready
    if(values[i][3]!='Ready') continue;
    
    //Verify if Email sent before to avoid resending it again
    if(values[i][4]!='Sent') continue;
    
    //Send Email (Email Adress, Title, Body)
    GmailApp.sendEmail(values[i][0], values[i][1], values[i][2]);
    
    //Mark sent to each email has been sent 
    sheet.getRange(2+parseInt(i), 5).setValue('Sent');
  }
}