WILL HAVE MY FIRST DOG SOON! ANY ADVICE WOULD BE HELPFUL!?

right first of all your have got a hard job on your hands, because the dog is two and its going to be hard to break the habits it already knows. dogs dont go in a litterbox/filterbox. you can use newspaper, but you have to wait and see first before you get carried away the dog might already know all this, you will only be able to tell when you get it back to yours and it does it then, or the shelter might know more about it, but you shouldnt be asking this question yet until you see what the dog turns out like