You have to get it apart first. The hole is because something did not fit between crank and case. It may not be the only damage. There may be cracks all the way around. Your crank needs to be rebuild, even if it looks good. The bearings would all have been damaged. That is the exit side of the spinning crank. So whatever it was, had to travel from the front to get there. If you have damage to both sides, I would look at picking up a used bottom end.