They lost about 5 million counts from the land they can no longer count in (Russia occupied) and at least 4.4 million to people leaving the country.
By all estimates, they've lost at most 200 000 soldiers (casualties aren't fatalities). 17 000 civilians have been confirmed killed, and the UN estimates that the total (including confirmed and unconfirmed civilian deaths) is 60-100k.
To emphasise: the war is horrible, but 12-13 million people have not been killed in the war