Writing help regarding Native America

Hiii, I'm white (Norwegian) and currently in the process of writing my AU and I want to be careful abt how I do it, so I wanted to hear opinions from people who know it better than I (like from people who are native)

Basically, so far as a place holder; USA and Canada are half siblings with Native Americe being their shared mother (no, there won't be romance with Native America and any colonizer nation, this is purely a political arrangement). However, I don't want to be insensetive about it, considering how many tribes that exist/existed.

So far I've gotten the suggestion of creating a political representative of Native America after the colonization started, but I would love to hear any other opinions, since I want to work this out without any offence in my writing :,3