Cardinal Angelo Becciu, the first cardinal ever prosecuted by the Vatican criminal court, was absolved of several other charges, and his nine co-defendants received some guilty verdicts and many acquittals.
He's old. Most likely he won't do real prison time, just "home" prison (I don't know the English word). Anyway, regarding your questions, most likely yes... With the exception of alcohol, that is allowed only on special events. Also, in theory a medical doctor (nutritionist) has to approve the meals. In practice I don't know, I've never been in jail.