The number of musical notes can vary depending on the musical system being used, but in Western music, there are traditionally 12 distinct notes within an octave.
These notes include: A, A♯ (B♭), B, C, C♯ (D♭), D, D♯ (E♭), E, F, F♯ (G♭), G, and G♯ (A♭). Each of these notes can be altered with sharps and flats, giving rise to a larger variety of pitches as you move through different octaves.
Additionally, other musical traditions around the world may have different systems of notes. For example, Indian classical music recognizes 22 microtones, known as ‘shruti’, which creates a more nuanced approach to pitch. Similarly, in some African music systems, there are unique tonal structures that define their scales.
In summary, while Western music utilizes a 12-note system per octave, the total number of musical notes can differ vastly depending on the cultural context and musical tradition in question.