I have a pitbull and I have no way of getting there . Can I take my dog on mta train?

Honestly no they won't allow it on the train unless it's a service dog.

Without carrier is risky . People see pitbull and are afraid just because of there bad rep. If you do ride the train put a muzzle on him so people don't exaggerate on his presence. Go when the rush is over the less people on train the better for him it can be a scary ride for them.

I don't have a carrier for the dog and I have an appointment tomorrow

If you have carrier that the dog can fit in yes. Nowadays I see people with dogs and no carrier.