Estimate power spectrum density by using pwelch function

Hello all, hope you having a nice day. I am trying to estimate the power spectrum density of 3 years of sea surface hourly data by using pwelch function, but I am struggling with deciding right window size and number of noverlap/nfft. If you have a tip on deciding such variables, please let me know and I would be really thankful if you can explain what they are. Thank you! (I attached the sea level data just in case)