During the French and Indian War, Native Americans sided with both England and France. Different tribes, and sometimes even individuals within the tribes, sided with different sides.
Among the advantages of siding with France was the fact that they were most tribes' main trading partner. As fur traders were often French, the French also had a stronger connection with the tribes. Many French people spoke native American languages, and many married Native women, even joining their tribes from time to time.
On the other hand, the English had a much more turbulent relationship with the Native Americans. However, the English were 20 times larger in number than the French, making them a more strategic partner. They had also promised land and other concessions to Native Americans who fought on their side through the Treaty of Easton.
If I were the leader of a tribe, I would side with the French, as they had a better track record of helping the Native Americans. This in fact is what most Native American tribes did.