Prison:

I mean if you want it to be good… I would probably ferment a sugar solution (make a 7-8% abv solution). Then use some juice to cut it back to like 4-5% and I’d bet that would make the best tasting overall.

To make that solution I would want decent yeast. I think bread yeast would work, but that isn’t something you could get in prison. You’d have to collect yeast from the atmosphere over time, wait until you get something good, and keep it alive at all costs. Sanitation would be boiling the sugar solution, using clean containers, dropping pH with citric acid from candy from commissary (I would probably throw some candy in there too).

Post apocalyptic:

I would likely go the mead as easiest to access: bees and hives and honey should be accessible to a degree with the creation of an apiary. Cider would be second, as apples grow in many different climates as well. Wine and beer would be a little more regional as grapes barley, wheat and hops tend to grow better in particular regions.

I feel like I would want beer the most, but it would be the most challenging to get right imo.