>>1806739what you need is a fork die
a good old bike shop will have one of these.
It will possibly be able to re-cut/ repair the threads.
the inverse tool for repairing/cutting threads in holes, like a bottom bracket shell, is called a 'tap'.
Technically they're not necessarily bicycle-specific tools but finding the right size will almost certainly be in a bike shop or amongst bike tools or from a bike tool maker.
A frame builder will certainly have one so if you have any frame builders locally you could contact them.
It's a very simple job so if you're friendly it shouldn't cost much, and they might even do it right away with you there for free, as long as you're clear that you just want to try it and you're under no illusions of it necessarily working.
If that does not work you should replace the fork. I could suggest all kinds of janky solutions but it's really very stupid. If it's a road bike, find a chromed fork for it, that should match.
