The conflict in Eastern Ukraine has been going on for many years, with the Ukranian government shelling and killing it's own people in a struggle against the predominantly Russian speaking population in these areas, many of whom identify as Russian and want separation from Ukraine, and an end to the persecution they have been facing since the previous Ukrainian government was overthrown in 2014 with help from the UK and other Western nations.
https://www.amnesty.org/en/latest/news/2015/02/ukraine-horror-civilian-bloodshed-indiscriminate-attacks/
The persecution of the Russian speaking people of Eastern Ukraine intensified under Zelensky. With this in mind, the protection of these 'Russian' people was a key reason why Putin decided to invade Eastern Ukraine. Putin is no angel, but neither is Zelensky who, together with his corrupt government, has bought much of this on himself and the people of Ukraine. But all we hear about here in our media is about how bad Putin is. They are both tyrants, Putin and Zelensky.
That said, Putin has stated on multiple occasions that he has zero interest in invading or launching attacks on anywhere else in Europe. Nor outside a Nuclear War which no one wins, does he have the capacity to do so. Yet it suits us here in the West to believe that Putin is the ultimate villain. It make huge amounts of money for our defence industry, and our support for Ukraine comes with conditions attached, that our companies get to make billions by rebuilding the country after the war, and we get access to Ukraine's huge amount of natural resources.
As they say, don't believe half of what you read on the news. There is always another side to the story.