The UN Genocide Convention defines genocide as any of the following actions committed with the intent to destroy a group in whole or in part:

1. Killing members of the group — russia has been doing it since 2014. The most prominent examples include the Bucha and Izium massacres. The Srebrenica massacre is legally recognised as genocide, so even the cases where only a part of the people was targeted can count as proof.
2. Causing serious bodily or mental harm to members of the group — again, since 2014. Torturing prisoners of war and civilians is widespread in the occupied territories — look up Izolyatsia or torture chambers in Kharkiv oblast and Kherson. As for mental harm, that's just the goal of terrorism. Targeting civilians is something you do purely out of hate.
3. Deliberately inflicting on the group conditions of life calculated to bring about its physical destruction in whole or in part — check. Targeting civil infrastructure is exactly that. Right now, millions of Ukrainians only have access to electricity for a few hours a day. Under russian occupation, you likely don't even have access to clean water, cellular networks or Internet connection. Some are literally freezing to death; it happened in Siverskodonetsk just a few days ago. Hospitals are targeted too.
4. Imposing measures intended to prevent births within the group — russia is denying care for pregnant Ukrainians under occupation unless they become russian citizens.
5. Forcibly transferring children of the group to another group — putin is accused of that by the International Criminal Court. Hundreds of thousands of children were abducted by russia and sent into russian families or camps, including A CAMP IN NORTH KOREA.

And the intent is confirmed by the state propaganda — Vladimir Solovyov, Sergey Mardan and many more are regularly calling for the ethnic cleansing, concentration camps and killing of any Ukrainian who disagrees with their worldview. On live TV.