You won't fix the powder coat, not without recoating. So yes it is a pro job. But if there's only some small marks you can touch with paint. The powder coat used should've had a RAL code (colour identification). If you know that you can get a paint the same colour.
If you don't know the exact colour, don't worry. You can get generic alloy silver touch ups that IMO can look quite good. But another avenue to explore - nail varnish. Loads of colours and as the bottle is clear you can see what the exact colour is. Just remember the clean and degrease before you apply any paint for maximum longevity