So decolonization is primarily a process for recently-colonized BIPOC (black indigenous people of color) to return to their traditions, sovereignty and landbase that was taken by force (and false treaties). In the case of non-native people, we can also engage in a process of decolonization to undo the harm caused to our own cultural groups in Europe from the forces of religious oppression, patriarchal dominance, the feudal system and other brutalities.
For approximately 2000 years (some say 5000), we have ALL been colonized, and decolonization seeks to understand ourselves as we existed before modern civilization, and that implementing holistic solutions and traditional earth-connected ways of life are vital to the survival of the human race. Decolonization is more of a process than a goal; the process varies from group to group; and it can re-center indigenous or earth-emergent worldviews in our movements for social transformation and the development of an economic system that serves rather than threatens our collective life on Earth.
Decolonization can be a complicated subject with many layers! My blog post "Decolonization: Meaning What Exactly?" is extremely useful for sorting out these definitions. www.stonecirclepress.com/blog-9658-ancient-spirit-rising/decolonization-meaning-what-exactly