Re: Can't update my mac without connecting to the app store but I need the last version to connect.....
I'd never heard of "reviewing" an Apple ID before using it, but apparently it is a thing—I assume the message you got was "This Apple ID has not yet been used with the iTunes Store. Please review your account information."? According to people on Apple's forums it may have something to do with verifying the payment method associated with the account—check out these threads (one older, one more recent)—they seem to be about what you're running up against :
If you google that error message itself, you'll get lots of references, though most of them seem to be related to getting the message on iOS rather than macOS; but it does seem to be related to setting a payment preference..
However if you can’t proceed with the "Review" process because the ML OS is too old, can you drop back into Recovery and install a newer OS version directly there? AFAICR one of the Recovery options is to install the latest OS your mac is compatible with: https://support.apple.com/en-us/HT204904.. Note that Apple recommends dropping into recovery with Command-R to avoid having the new OS tied to the old Apple ID, but then seems to say that that the option to install a newer OS may not be available in Recovery prior to Sierra..?!?
Honestly, though, when I run into stupid stuff like this I usually call Apple tech support directly—they should be ready, willing, and able to suss it out and step you through whatever process is necessary..