There are many, many places where people can go to learn about stuttering! Here is a (non-exhaustive) list of useful resources:
Your country’s association for people who stutter. The Canadian Stuttering Association has some valuable resources for people who stutter in Canada. Other countries’ equivalent organizations include the National Stuttering Association in the USA, the British Stammering Association in the UK, the Stuttering Association for the Young in Australia, or the International Stuttering Association worldwide. Of course, you can always look at websites for other countries’ organizations for more information!
Books published by scientists, speech-language pathologists, or people who stutter. Interesting books include:
Self-Therapy for the Stutterer, by Malcolm Fraser (a guidebook on how to manage a stutter - by a stutterer!)
Out With It: How Stuttering Helped Me Find My Voice, by Katharine Preston (a memoir)
Stuttering: A Life Bound Up In Words, by Marty Jezer (a memoir)
Stuttering: Inspiring Stories and Professional Wisdom, by Taro Alexander, Joel Korte, and Phil Schneider (a compilation of essays about stuttering by stutterers, disability activists and stuttering treatment professionals)
Who Do You See? The Struggles of a Teenager Who Stutters, by Sean George (informative, normalizing the experiences of teens who stutter)
Local support groups. Your community may have a meetup group for people who stutter, or parents of people who stutter. While these groups may not be as useful for finding information about stuttering itself, they will provide a lot of information and guidance from people’s lived experiences of stuttering.