Do you mean ejector pin marks? In that case it depends: some are raised, in which case you can scrape, file or sand them smooth; if they’re recessed, filling is usually the only real option — unless the part or area is small enough that you can scrape, file or sand down the whole part around the mark.
First question is " will you be able to see it, when the model is finished?" Sounds silly, but I've filled many an injector pin mark, only to cover it up later in the assembly.
As above, if it stands above the surface, scrape or file down. If recessed, then putty & sand down flat. I know that some people use CA to fill pin marks, bit I've never really found that satisfactory.
Dave
Very good point. Don’t waste time correcting things that are entirely out of sight (and don’t interfere with fit of parts — find my Lightning F.6 model on this site for some thoughts on that )
I’ve tried that too, and don’t like the method much. Cured superglue is much harder than plastic, in my experience, which is exactly what you don’t want. I much prefer putty from a tube.