Ukrainians are a nation. The nation includes both those who have Ukrainian as first language, and those who have Russian as first language, just as the Irish nation includes many who have English as first language.
Ukrainians are a nation long oppressed under Russian and other foreign rule. They have a right to self-determination.
Within Ukraine, there is exceptionally sharp class inequality. A few oligarchs are hugely wealthy and pay few taxes. The majority are much poorer even than in neighbouring Belarus or Romania.