How Do We Find the 12 Different Tones?

Between all note letters, we have a whole step, sor two half steps. The black keys on the piano give us sharps or flats between letters. So what is a minor third from g b flat? A b flat, of course. We have 12 notes, 12 different frequencies. Before we to doubling or halfing to find octaves, let's count them on our fingers so we can readily identify the 12 different tones using our seven letters and five sharps or flats.