Is there any kind of martingales that you can use for dressage and also, are you allowed to use a flash noseband? Sorry to sound like an idiot but I'm completely new to dressage
No martingale, horse must wear a noseband. I've attached a link here and it takes you to the rules page of British dressage. It will tell you types of bit you can use, and other equipment that is allowed....more important it also tells you what you can't use. You can download the various sections.