General kayak & canoe padding groups
Solo Canoeist – a public group with over 8k members, active with plenty of regular posts, generally helpful and on topic.
Paddling destination groups
Algonquin Park – located in Ontario this park is a favorite destination for hikers and paddlers. This is a public group with over 60k members so lots of posts on many topics. You might have to search but there’s plenty of information on paddling and routes.
Canoe and kayak building, repairs & maintenance
Canoe Paddle Makers – over 5k members in this paddle-making group. Way beyond my craftsmanship but lots of useful information and helpful content.