I just don’t understand, he says to go to reservations and talk to actual Indigenous people but I thought Indigenous people came up with, and advocate for, Landback

Of course, he’s just dodging the issue; indigenous people did come up and advocate for the movement. If ye look at the mostly untouched wikipedia page, it says this…

Land Back was introduced in 2018 by Arnell Tailfeathers, a member of the Blood Tribe, a nation within the Blackfoot Confederacy. It then quickly became a hashtag (#LandBack), and now appears in artwork, on clothes and in beadwork. These creations are often used to raise funds to support water protectors and land defenders who protest against oil pipelines in North America.[8]

Nextly

His statement about Indigenous sovereignty also doesn’t make sense to me because I don’t know what he means by that…

Just look at my above statement, as many people have said, at best, mistaken in the belief that western NGOs mainly created the Landback movement, at worst, willfully ignorant and malicious…