You do not need to fit a pre-defined functional form to your data point, but you can draw a smooth curve though most of the data. You should describe physically why the curves have the shape they do in your lab report. If you are sharp, you can use these plots to numerically determine the components of the earth's magnetic field. The third part, Larmor Precession is both tricky and exciting. Save time at the end of the lab to do this.
Some students run out of time.
Again, your goal here is to find the signal and carefully draw a sketch, with units and such. Make you best effort at determining the oscillation frequency. If you have time, try and see how the frequency depends upon the applied field. Take time to describe the quantum physics your observations in your lab report. You are essentially watching a large collection of atoms precessing in phase.