I think the hardest kayak paddling stroke to do correctly is the forward stroke. Over 90% of paddlers I see out there are not doing it correctly.
The forward stroke looks easy. Yet most people are “pulling” with their arms or shoulders instead of engaging their torso. In any kayak paddle stroke, the torso must be engaged! You begin with an upright body position. Not too forward nor back. Then extend your arm, inserting the paddle blade at your foot. Twist your torso outward keeping your arm relatively fixed. When the paddle blade reaches a point about even with your waist, it’s time to remove the blade. And you also engage your feet! To get the most out of your stroke, use pressure on your foot brace on the same side as you’re paddling for that stroke!
Here is a great video by Werner Paddles pro Danny Mongno. He does a great job of explaining the subtleties of the forward stroke!