Well if you have Internet I'm sure you can use a online compiler. I don't have a chrome book myself but I believe everything is done online, your better of getting a cheap laptop son be sure that it runs code::blocks then getting the chrome book and having no compiler offline or something.
I'm not 100% sure but I don't think so
Chrome OS does not support Code::Blocks. It only runs "chrome apps" from the chrome web store, like the browser does. Like CaptainBlastXD said, you can use an online compiler and just save the file and use it on another computer.