A big part of stuttering comes out of the idea that you can’t speak fluent and therefore have to DO something for it. But that effort, forcing and doing your best actually produces more stuttering.
Solution? Realise you’re already a fluent speaker and that there’s nothing to accomplish. There’s nothing to attain. There’s nothing to strive for.
Once you understand this, you’ll no longer feel the urge to try to control every word you speak. And that’s the moment that everything will start flowing more and more, including your speech.