Fourier transform problem

Hi All
I’m a mathematica new user.
I have a 2D table, recording some transient data: data={{time1,pressure1},{time2,pressure2},…}, time interval is the same. The peak frequency is my interest,which buried in the noisy signal.
How can I transform it into frequency domain and plot the data. I also want to use hanning window function.

Check Help > Wolfram Documentation > Periodogram

Thank you