OK, I have no idea where you found concepts like "it makes my sound not spread so much from where it should be".
All sound is made up of waves. Those waves ripple at different frequencies. Frequency = pitch. High frequency = high pitch.
An EQ adjusts the relative levels (amplitude, loudness) of different frequencies. That's all. A three-band EQ is a set of knobs that says Low, Medium, and High, and they adjust the relative levels of the low, med., and high frequency ranges. A graphic or parametric EQ will allow you to control the levels of much more specific frequency selections. The "bands" are specific pre-chosen frequencies or groups of frequencies. For every kind of EQ except parametric, the more bands = the more specific you can get in your control. Parametric is a more advanced system that you'll have to learn about later.
If the scratchy finger noise exists in a specific frequency range, and your EQ has control over that specific range, then yes you can reduce the level of those sounds. But not eliminate them completely, not without seriously altering the rest of your signal.
