-든(지) after a question word means 'no matter which', so 어디든 가다 is going anywhere whatever — six of these lines use it (어디든 갈 수 있어요 이거면, with this I can go anywhere). 언제든 갈 준비는 되어 있다 does the same with time: ready to go at any moment. 어찌 됐든 is a separate set phrase, 'either way, whatever happens'.