Ukraine’s current government came about because of the Euromaidan uprising, where a bunch of armed men stormed government buildings in the capital in the west, and declared a new, pro-Western government.
What I read is that Ukraine's parliament voted to remove Yanukovych from the presidency, and hold a new presidential election.
I think it would be good if Ukraine could have new elections, with all regions that are legally part of Ukraine being able to vote. That would include Crimea, the Donbas, Zaporizhzhia, and Kherson.
I guess the reason that's currently impossible is because the Kremlin gave weapons, troops, and assistance to rebels in the Donbas, to help them violently take control of the region. Then Russia increased its invasion in 2022.