As you say, Canada had a 7 year process to do just this. It was chaired by Murray Sinclair. Sinclair is an Indigenous man with a lot of standing in the Indigenous community and in broader Canadian society. He was an associate chief justice in Manitoba, and a federal senator.
It produced a bunch of documentary evidence, and a bunch of recommendations.
If people want action on this, following those recommendations would be a start. As it happens, one of the recommendations is funding for the ground-penetrating radar that is turning up these burial sites. While that recommendation was ignored at the time it was made, provinces are now funding it. We can expect more of these stories to come out. We don't need to start from scratch, we just need to make progress on the existing findings.
They've been vocal about funding it now that it's in the media, they haven't funded anything yet.
The two announcements I'm thinking of are Ontario's ($10M over 3 years) and Alberta's $8M (available in $150K grants, application process for the next 6 months). The fact that there are dollar amounts, timelines, and they're offered by a political party holding a majority in the legislature makes me think it's likely to actually happen.
"It may sound crazy but North America was previously inhabited and yeah, what happened to the previous inhabitants?"
It reminds me of the situation the European Union has going on with Hungary. How do you claim moral superiority as a Western country when you have none?
China's call for an international review is a craven political action designed to embarrass us on the international stage, but frankly we should be embarrassed (and a lot more). I would support using something like the International Criminal Court or the UN Commission on Human Rights to help produce findings on what went on and what can be done to start to heal. We could set an example for the world on how to reconcile on these issues and find a path forward.