There is no historical evidence to suggest that Vikings routinely burned their boats as a strategic tactic, similar to the legend associated with Hernán Cortés. The idea of burning boats to eliminate the option of retreat seems to be more specifically connected to Cortés' expedition in the early 16th century.
Vikings were known for their seafaring skills and used their boats (often called longships) for exploration, trade, and raids. They were pragmatic and resourceful, and it's unlikely that they would intentionally destroy a valuable asset like a seaworthy vessel without good reason.
While Vikings did engage in surprise attacks and raids, the idea of burning their own boats to prevent retreat doesn't align with their general tactics and strategies. Vikings were known for their flexibility and adaptability in different situations, and they would likely have kept their options open for a quick escape if needed.
It's important to note that historical information about the Vikings comes from a variety of sources, including sagas, historical accounts, and archaeological findings. While there is much we know about Viking culture and activities, some aspects remain speculative or unclear due to gaps in historical records.