Hiccup rides no dragon before meeting Toothless in the 2010 film How to Train Your Dragon.
At the start of the film, Hiccup is a young Viking who lives in Berk and wants to help defend the village from dragon attacks. He lacks the physical strength and traditional combat skills admired by the other Vikings, so he works with Gobber in the forge and experiments with inventions instead of riding dragons.
Hiccup’s relationship with Toothless begins after he brings down a Night Fury during a raid. Rather than killing the injured dragon, Hiccup secretly helps him recover. Their early flights become the foundation of Hiccup’s understanding of dragon behavior and eventually transform the culture of Berk.
This fact can be confused with events later in the film or with the sequel, when several Vikings ride dragons. Astrid rides Stormfly, Fishlegs rides Meatlug, and the twins ride the Hideous Zippleback. Hiccup’s first dragon-riding partnership is specifically with Toothless.