Registration is key.
I teach singers what chest register (the register used in speech), head register (sometimes referred to as falsetto), and mix (both registers used simultaneously) are, and how they might be used in their chosen style. Some styles are chest register dominant. Some are head register dominant. Most styles use both registers to varying degrees. A few styles separate the two to such an extent that only one register is heard or felt. (eg. belting (singing loudly in chest register), or yodeling in country music (separating and alternating chest and head)
Describing the sound of chest voice and head voice in print is inadequate. I demonstrate them for students so that they can recognize the function through the experience of sound, sight, and physical sensation (feel).
Contemporary styles are, for the most part, chest register dominant. Dominant yes, but not to the exclusion of head register (falsetto).
Classical styles are, for the most part, head register dominant. Dominant yes, but usually, not to the exclusion of chest register. (Some high, light sopranos and most counter-tenors use head register almost exclusively.)
I teach singers how to belt when appropriate, mix when appropriate, use head register when appropriate, and recognize the usefulness of each, depending on the style. I teach how to sing in a healthy way, with a functional, scientifically sound approach, toward what you wish to accomplish.
If you have any questions, contact me.
All the best on your musical journey.
Mark Hoeler