analyse pcm data from a wav file with a fft

I will analyse a wav file server side with an fft algorithm.

When read the pcm data from the wav file i get a Float32Array, but i think for a fft calculation i need an Array with Float32Arrays inside. Each of this array represent a sample with a specific size (1024, 2048 ...) is this correct?

How can i perform a fft calculation on pcm data from a wav audio file? The length of the Float32Array that i get when i read the pcm data form the wav file is 219036.

[
[0.5,0.5,-0.5,-0.5],
[0.3,0.3,-0.3,-0.3]
]

I will do this in node.js

Thank you for all thoughts

via Aron