What is the best way to play music through speakers
You need a lot more than just that CODEC chip to generate audio. You need something to control it, and something to amplify the sound to drive the speakers.

That means some microcontroller based system (maybe an Arduino or something like that) and a power amplifier board.  Oh, and of course enough battery power to run it all, and enough programming and electronics experience to get the whole lot working together.

Better off using a cheap MP3 player and a small power amplifier - maybe the one you threw away from the iPod dock?