Once you have legally secured a true variable font (like Crimson Variable), installation is slightly different than standard fonts.
Minion Variable Concept-Roman Font: Elevate Your Typography with this Elegant Font
Many "free download" sites host one of three things:
This is the magic of Minion. It automatically adjusts the thickness and spacing of the letters based on the font size. Small text becomes more robust for readability, while large display text becomes more elegant and high-contrast.