How do you create a plot outside of Audacity?

I have exported the Audacity plot spectrum (FF) data into excel and then plotted it but the peaks look nothing like what Audacity shows. Ideally I would like a graph that shows the fundamental frequency and then the harmonics.
thank you in advance!

Perhaps you could post screenshots of the Excel graph, and the “Plot Spectrum” graph, so that we can see what you mean.
See here for how to attach screenshots to a forum post: