at later dungeons you're really not supposed to do it blind (well you can, but you should find people who want to do it with you).

FF14, especially later on, heavily depend on specific mechanics. Things you must do, levers you must press, you must look away from the boss at certain points, adds you must kill or you'll get instantly killed, etc. Remember the Ifrit Nail that you have to kill or your party get wiped? Like that x1000

Most people suggest at least reading about dungeons before doing it first time, but even if you not do that, just say to your party that you're new and would like to know the boss mechanics, and most people will help you.