I’m building a web page’s CSS, following a video course. I downloaded the Inter font from fonts.google.com, and the download included multiple sizes for each style such as:

Inter_18pt-Regular.ttf
Inter_24pt-Regular.ttf
Inter_28pt-Regular.ttf

Why does it include multiple sizes? I guess if I use font size 20pt on my page it will scale whichever font I pick up or down to the target size. Should I pick the font file that’s closest to the desired size? Or are these intended to be used together somehow?