Bring that amount in cash, plus a credit or debit card, and inform your bank that you want to make sure the card will work in Taiwan. ATMs are nice if they work, but until you’ve tried it once in your destination country, you won’t know whether the card is actually accepted, and what would you do if it were rejected? You’ll need a backup plan. Bring enough cash to get you through a few weeks at least, and consider setting up a bank account here as soon as you can, so that in a pinch you could have a relative or friend wire you money, which would then be available a few days later. You’ll probably need an ARC (Alien Resident Certificate) to open an account though. Don’t count on your home bank giving you good service here unless you arrange it in advance. Note that BofA does NOT have a retail presence here.
TC’s aren’t accepted by most retailers here, and even many banks reject them, so the fees involved (which used to be justified, given the better exchange rates and the convenience) aren’t really worth it any more in my opinion.
Split your cash into various save locations on you, in big bills, like inside a money belt, your wallet, another secure pocket, and so on. I like the internal pockets on 5.11 Tactical shirts, and the extra, knee-height pockets on their pants, for instance, as well as thin travel wallets that attach to your belt but flip to the inside of your pants, waist-level nylon pockets with a belt that you put on under your pants, and so on. The passport carriers that hang around your neck are an easier target for thieves, especially if you fall asleep in the airport. One friend lost everything that way, some 16+ years ago here.