its called a fly mask and its made out of mesh so they can see through it and the purpose is to keep they flies out of its eyes. its better for the horse in the long run.
I would start out with simply training the horse to drive from behind in-hand. When you're sure the horse is fine with that, start having someone else bring the cart behind the horse (not hitched up). Then hitch the horse and ask for nothing but stan...
I am going to assume, since the rest of your questions have to do with harnesses, that you are referring to the driving bit and the check bit. The driving bit is what is attached to the reins and help the driver steer the horse. The check bit holds a...