Shooting it?
There are ways to repair the damage. You are not supposed to drill all the way through. A gunsmith who works on BP guns can take care of it. It will not be cheap a thing to do.
The very best way for you to get through this is for you to get yourself a new barrell.
The old barrell can be used to make carbines and pistols by those who have the tooling and the experience. You have to tell them what is wrong with the barrell. They will cut what they need from the barrell, thread it, plug the breech according to their kit or need, and life will go on.
You can shoot the old barrell with BP or Pyrodex, but it will vent through the hole. It will not blow up if loaded properly, but it will create a hazard and it will begin to erode and weaken the barrell wall if unplugged. You can also be blinded or seriously injured by the pressure coming through that hole. I dont know how big the hole is, but I do know you dont need a hole in your barrell ! If you try to plug the hole yourself with a threaded bolt, it will hold for a while, but might eject forcefully and unexpectedly at bullet speeds. If the bolt is too short, an erosion will begin inside of the barrell and it will weaken the barrell wall. Eventually that will fail under pressure or cause the screw to eject at bullet speed. If the screw is too long, you are creating an obstruction in the bore that will give you trouble loading the weapon, and it would not be a good thing to pull the trigger if there is a large airspace between the load and the charge. Not safe to do.
Buy another barrel and put the new barrell on your piece. Have sights dovetailed into place or soldered on. If you have a thick barrell, let the gunsmith drill and tap if you want.
Mark the old barrell and tag it with an explaination of it's condition and sell or trade it to a kit maker or gun maker for cutting.
There is no reason to waste time and money and engage in risky shooting on a damaged barrell. There are too many barrells for sale out there. They are cheap enough and it is the safest course of action. Remeber, you are dealing with massive pressures and projectiles here. It can cause serious injury. It can even cause death. Just get another barrell.