Ukraine does not have to give autonomy to Donbass, and Russia did not want autonomy for the region, it wanted the secession of the region from Ukraine. The one destroying is Russia, no one has done more damage to eastern Ukrainian cities than Russia. Look at what they did to Mariupol and Bakhmut.
Russia gave Crimea away willingly to Ukraine in 1954, and in 1994 signed the Budapest Memorandum where it agreed to respect Ukraine's borders and sovereignty. This is all that matters. Also, no one can know for sure what the people in Crimea want, Russia held an illegal, sham referendum.
There are left-wingers who support imperialism, and the people in the far left and the far right have one thing in common, they usually support Putin and his unjustified aggression.
The reason Ukraine wants to join NATO is because Russia can't mind its own damn business. Russia should start minding its own business instead of dictating what other countries do.