Does boiling your water remove minerals? The short answer is no. In fact, it might even do the opposite.
Why Minerals Stay Put
When you boil water, the liquid turns into steam, but the minerals (like calcium, magnesium, and sodium) are "heavy" and stable. They don't evaporate with the steam. As water escapes the pot, the concentration of minerals in the remaining liquid actually increases.
Boiling vs. Distilling
Boiling is for disinfection. It kills bacteria, viruses, and parasites to make water safe to drink.
Distillation is for purification. To remove minerals, you must collect the steam and turn it back into liquid in a separate container, leaving the minerals behind.
What About the White Flakes?
If you see white residue (limescale) in your kettle, that is some of the minerals "crashing out" of the water due to the heat. While this removes a tiny fraction from the liquid, the water itself remains mineral-rich.
Summary
Kills Germs? Yes.
Removes Minerals? No.
Removes Chemicals/Metals? No.
If you need truly mineral-free water for a medical device or appliance, use distilled water or a reverse osmosis system instead of just boiling.