Boiling water kills bacteria but does absolutely nothing to dissolved solids. It actually concentrates them as steam escapes. So no, a kettle won’t fix your mineral problem.
Standard pitcher filters (like Brita) only catch big chunks like sediment and chlorine. They ignore dissolved solids like they’re not even there. Rude.
If you want a cheap hack, you can try “precipitation” by adding baking soda to hard water—it makes calcium carbonate settle out. But it’s messy and turns your water into a science experiment. Fun? Yes. Practical? Not really.