What are the first indications that Charles and Hal are not suited for the Yukon in the call of the wild?

In "The Call of the Wild," Charles and Hal display a lack of preparedness for the harsh conditions of the Yukon, evident in their poorly organized supplies and overloading of their sled. They demonstrate ignorance of the needs of their dogs, often pushing them beyond their limits and showing no understanding of the animals' capabilities. Additionally, their impatience and disregard for the advice of experienced travelers highlight their unsuitability for survival in such a challenging environment.