For potty training, I would keep him where you can supervise as puppies at 9 weeks can get into allot more trouble (like chewing on electric cords) than just doing No 2 in the house when out of site. So, now that you have Indy where you can watch him, you can start work on potty training. Whenever he gets up from a nap or finishes eating, take him outside. Anticipate when you think he will need to go potty. If you take him out and he just goes a little bit praise him, but I would keep him outside (esp if you know he needs to go more) longer. Don't get in a hurry to take him back inside as you already know what the result will be. If he just won't focus and finish his business and you need to go back inside, it is really important you keep Indy with you so you can watch him and get to him before he has an accident. If you notice his is looking for a place to go, grab him and take him back outside and give him his potty command and be patient. Even if he is in the middle of doing No 2 in the house, still pick him up and take him outside to finish. Again praise him when he goes outside. Don't make an issue of his accident inside. He is still a baby and learning. I think with some perserverance you can work through this one fairly soon.
For leash training, you need to get him leash trained soon as it is easier now than later. I start with a light weight puppy collar and a light weight leash. Put collar and leash on him and let him drag the leash around (you should be where you can watch him). Eventually he will get used to the leash, then pick it up and don't pull him, let him lead you around. Eventually when he gets used to that you should be able to start walking him. Now you can start working on no pulling. If he pulls you, stop, when the leash slackens then you can start walking again. You may be doing allot of starting and stopping, but this will help you later on when he is older and can drag you down the street. Remember, he is a puppy and all this work should be fun and upbeat. No scolding or correction, just lots of praise when he does something you want him to do. GSPs are smart and catch on really fast. On other thing, do not let him chew on or bite the leash. That is a really bad habit for them to get into. If he puts his mouth on the leash say no, and remove the leash from his mouth. Again, it is easier to fix this not than later.
Good Luck and keep us posted on progress.