I would also agree with Priya, but check over those spots. what may look like a 'donut' sized hole usually ends up being bigger after you've ground to good, solid, proper thinkness metal.
Anything is repairable, depending on skills and time, and how much effort you want to put into it. but I see your point - this is (possibly) beyond your skills, and seems worrisome.
When you say 'a spot' we talking like a quarter sized hole, donut sized hole or can you crawl thru it?
it would be great if you would post some really good pics of the areas.