No. Although a good portion of them supported the British, you did have a few like the Oneida and the Catawba that supported the American rebels. For the most part, it was mainly to due to circumstances and convenience. The Catawba were almost entirely surrounded by colonists and the Oneida were just near the border, very close to whig-leaning communities, unlike other tribes that had some measure of distance away from colonists. Even then, relations were tenuous at best. Not all Oneida supported the patriots. There was a lot of internal strife within many native communities. Even though though the Americans saw the Cherokee joining the British with the attacks in July of 1776, many Cherokee actually opposed violence and sought neutrality -as did many other tribes. A lot of the more militant and "warlike" were lead by the younger men, in many cases the elders tended to support neutrality.

For the most part, support for the British stemmed from two things: trade and protection. Lots of tribes like the Cherokee and Shawnee benefitted from the British system as part of the deerskin trade, one of the major economic livelihoods of many tribes. They also wanted British protection against the continuing encroachment from American colonists pushing to the west. Many of them saw the possibility of even more land erosion with an American victory. Many of the British Indian Agents were also their main suppliers of gunpowder, lead, and other necessities.

While the British were some of old partners for many natives, I'll make it clear that the natives didn't favor them purely out of favoritism. When the French were the other big power on the continent, often natives played the two powers against each other, trying to play the "middle" to their advantage. By the 1770s, the British were the biggest power in the eastern half of the continent, and many natives had seen British power first hand in the French and Indian War, so when they faced these colonial upstarts from Philly they went with the biggest power they still knew: the British. Not to mention, yet again, they saw the Americans as more of a threat to their wellbeing. Especially with those like the Cherokee, who had been losing lands to American settlers in western NC, SC, and VA.

Colin Calloway's The American Revolution in Indian Country, James O'Donnell's Southern Indians in the American Revolution, Richard Blackmon The Dark and Bloody Ground, Richard White The Middle Ground,

I've answered this a bit more in these threads from before. If you have any more questions, I'll be happy to answer them once i get back from work.
https://www.reddit.com/r/AskHistorians/comments/9rtzhh/what_were_the_native_americans_perspective_of_the/