Highly recommend reading the Red Deal, which is written by Indigenous socialists on what they think decolonisation should entail.

https://therednation.org/about-maisha/

Also keep in mind that every Indigenous community has different views on colonialism and the land and sovereignty issue. Some really just want to be left alone on their historical territory, others actively want to work with non-Indigenous people living on and around their ancestral land, and everything in between with tons of nuance. There is no singular "Indigenous attitide" on this though there does tend to be similar schools of thought. The most important thing in decolonization is to listen to all of them and respect their wishes.