Your translation is almost perfect! If I add some explanations from a point of grammar, 「～ねばならない」 means "have to ~" or "must ~". So the phrase:「暮らしていかねばならない」 can be divided into these two parts:「暮らしていく」+「～ねばならない」. So the second sentence means "people will/would (still) have to continue to live in fear. " I hope you have a great time with a Japanese RPG!

I'm not a native speaker, and they probably know better than I do, but another way to think about is to look at the grammatical construction for "must": http://www.guidetojapanese.org/learn/grammar/must Basically, for "must not do X" you use "if you do X, it won't come to anything (good)": "X-eba naranai" or "X-eba ikenai". The -eba form is one of the conditionals. For "must do X", you use a double negation and negate X as well, as in "if you don't do X, it won't come to anything". If you negate "iku", you get "ikanai", and the conditional is "ikanakereba", as Shuntaro-san has already said. That's why ku changes to ka. The vowel a followed by n already indicates the negation, so shortening it to "ikan(aker)eba" doesn't loose any important information: both the negation and the conditional indicators are still clearly recognizable. If you want to learn more about Japanese grammar, I can only recommend reading all of http://www.guidetojapanese.org/. I found it incredibly helpful.