The books of S.Plokhy are all worth a read:-
The Gates of Europe (A history of Ukraine)
Lost Kingdom (History of Russian Nationalism)
The Origins of the Slavic Nations (Ukraine, Russia, Belarus)
Chernobyl
The great American historian T.Snyder has written Bloodland (History of Central Eastern Europe between Hitler and Stalin)
PLUS
A Very Short History of Ukraine by A.Clayton
Red Famine by A.Applebaum ( a really great book)
Borderland by A.Reid (A Journey through the history of Ukraine)
The Border (The story of all of Russia's borders)
Ukraine and Russia by P.D'Anien (2019)
I have avoided books, pamphlets etc rushed off the presses in the wake of the Russian invasion as many are just rehashes of other people's work. You are better advised to read a newspaper of proven quality, watch television news from a broadcaster you trust, or read a weekly magazine you trust (In Britain that is The Economist for an erudite and balanced view).