I used a saw like that when I was a kid. I wonder what happened to it. Probably lost in one move or another. Many of Dad’s old tools were, alas.

I only ever learned to sharpen carpenter’s handsaws, from 5 ½” to 12 point. You’d need a specialized saw set for those teeth. You’ll also want to build yourself a sharpening frame. I don’t know how to describe one without pictures. But Google is your friend.