Redirect to a routed page when form submitted

This should be obvious but I can’t quite suss it.

I have routes set up where there’s an ID in the URL. It all works perfectly. I have a simple one-input form where an ID can be entered. I want to go to the URL with that ID included.

eg. /details/abc will be shown when ‘abc’ is submitted in the form.

What’s the best way to achieve this?