On a technical level, do research on Ronald Webster. He founded HCRI before it closed and has helped a ton of people. From a parent, do your best to remind him the stutter doesn’t define who he is. Hes young and hopefully he grows out of it and it isn’t severe, but always empower him to be confident and say what he wants to say, no matter how long it might take. I’m just saying this from a young man’s perspective who just went through 20 years of school and struggling—what I wish was instilled in me from a young age.