Frequency describes how often something repeats. Hertz, or Hz, means cycles per second. A 200 Hz tone vibrates 200 times every second.
A tone and a beat are different things. The pitch of a sound comes from its frequency. A rhythm describes a pattern over time. In a binaural listening experience, the difference between two tones is also expressed in hertz.
You do not need to memorize a scale to begin. Start with a comfortable sound and a simple intention: a break, a work session, or a moment to settle.