Are you familiar with how to load 120 film in the camera's film back? I was assuming you were familiar with the camera as you specifically asked about a "light leak". Its not a "light leak" if its caused by user error. The camera has a horizontal cloth shutter... some of the patterns in the samples indicate a shutter problem. Hence my suggestion to check the shutter. We are now looking at "user-error", "light leak", "processing error", "camera problem", "film handling error"... too many variables.
If you should give us as much detail as possible if you want help.