You can eat them if they have the nutrients you need. Non-carbon-based just means it won’t use carbon as the foundation of its molecular and cellular workings. By mass, there’s relatively little carbon in living organisms and on earth, so whatever’s out there could still use carbon and other elements enough that it has something we could eat. There’s barely any telling what kinds of chemicals will be found in an organism like that, but it could easily be a mix of things we can digest and things we can’t. Even carbon-based life is like that. Wood for example is biologically very similar to us, but is mainly made of cellulose, which we can’t really digest at all.

yes, if it fits.