Well, I'm no expert on decolonization and can only speak for the US, so while I can't give a full layout of what will be needed, there are a few things I can almost (70-80% certainty) guarantee will be needed in the US.

The US will need to dissolve completely. By that I mean:

1. The flag completely replaced. Each stripe represents stolen land (the thirteen colonies). Each star is also stolen land (each state).
2. The state borders completely redrawn to better reflect the historical lands held by indigenous peoples. This must be decided by indigenous peoples and not whites or anyone else. If colonized peoples decide it to be so, this may mean regions within the US become completely separate and sovereign nations. Also, since many historical lands spread across Canada and Mexico, the borders of those areas may need redrawing once liberation is achieved, though I am neither Canadian nor Mexican and have essentially no authoritative knowledge on how that might happen.
3. The newly formed government(s) must include and be agreed upon by native peoples.
4. Economic reparations to colonized peoples is a must, and can be financed by assets seized from the bourgeoisie during revolution. This must also include formal apologies and recognition of the sins of colonizers in history texts, courses, and within new documentation for the newly established government(s).

I realize there is likely more, but I am not knowledgeable enough to speak beyond this so far, and I may be wrong on even the points I addressed (so please correct me if you find error, I won't be offended). If comrades have more to add, do so please!

As for other things I've learned from talking with indigenous and colonized people, I can also add:

1. Contrary to rightist fearmongering, "land back" doesn't mean the deportation of whites back to Europe. That is largely a narrative driven by right wingers to instill fear into whites that they might lose their homes and livelihood or whatever if land back were achieved. However, I haven't met any indigenous communist who seriously thought displacing millions of people was a good idea. Instead, whites will need to get used to "not being on top" of others, will need to get used to not getting special treatment when dealing with government and the authorities, with education, with employment, and everything else they get preference in.
2. This also (mostly) applies to the non-indigenous victims of colonization, blacks won't be deported or displaced, and in fact will achieve further liberation through the dissolution and replacement of white supremacist institutions like (everything basically) the prison system, the policing system, education system, etc.

There is certainly more to it, but again, I am not a final authority on this. These are just a few points I personally have a good deal of confidence (maybe 70-80% confidence) in. Comrades, if I am wrong about something, please let me know, and definitely add more to this incomplete list.