Remove dent/scratch from macbook pro edge

it's anodized aluminum. You can't replicate the finish (any modifications will be more shiny than original).

You can remove the peaks of the burr by carefully filing it down with a metal file. Sandpaper is not as good, because it will make the whole neighborhood around it shiny as well.

You can't replace removed material unless you want to use some kind of auto body filler material and repaint it.

I suggest you leave it alone. Anything you do will just make it worse.