Cotter crank, or Cotterless Crank?

If the crankset has cotters, then it should be steel. It will be hard to break that, although perhaps you'll be able to successfully bend it.

Upload some photos and close-ups to your Album/Gallery page:
https://www.bikeforums.net/g/user/500264

It is quite possible that even if it is in pristine condition, it is not an extremely valuable bike. And, in that case, have at it to make it into your dream bike.

Wheels are likely to take more of a beating than the crankset, but you've likely got 36 spoke wheels which should be reasonably good. Steel rims?