There are estimated to be over 12,000 Mastodon instances (servers) in the Fediverse, but there is only one North American Native/Indigenous instance with the high reliability record of TurtleIsland.social.

TurtleIsland.social

Native/Indigenous owned and operated for Native/Indigenous people in North America. TurtleIsland.social is ad-free, corporate-free, bigotry-free, and culture respectful.
https://turtleisland.social/about

TurtleIsland.social is highly recommended as the best, most reliable choice you can make in choosing a Fediverse instance. It is professionally hosted and has developer level support. It is a 5 nines site, in other words fully operational 99.999% of the time — an average of less than 6 minutes downtime per year. It is fully capable of celebrity or high demand users. It doesn’t get better than this.

Turtle Island also has non-Mastodon Native/Indigenous instances

Akkoma (Twitter-like) TurtleIsland.rocks
Pixelfed (Instagram-like) TurtleIsland.buzz

Thanks!
-Yehuda