According to the input N value store those calculated twiddle factors in a ram block.(convert those cordic values to fixed point values according to your project and how you are going to use) As in FFT at each stage and each butterfly twiddle factor changes, call particular address location from that ram block (according to the stage and which butterfly you are going to calculate)
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think about algorithm how you are going to call those twiddle factors after storing in a ram block