There would have been no conflict or invasion at all if the US & NATO weren't trying to damage Russia by imposing a financial & monetary blockade, politically controlling their closest & most economically important ally, & blowing up their natural gas line (which would have ensured peaceful economic trade relations with Europe). The US is willing to drive up energy costs in Europe & leave people freezing, as well as risk nuclear war, in order to overthrow a country that is no threat to anything except dollar dominance.
Donbas was already ethnically Russian because of migrations that happened during the Soviet Union. That part of Ukraine is particularly economically & strategically important to Russia. The people there in recent years actually voted to join Russia & Russia said no but did offer a peace deal to Ukraine that would help them to secure independence. Zelensky has banned all political opposition, nationalized all media in the country, & has imposed a draft so that he can enslave people to fight this war for the US (even people who are opposed to the entire conflict). The violations of the agreement not to move NATO east were almost completely ignored by Russia until Ukraine was involved, which Russia repeatedly said was the brightest of red lines. The US goal is to overthrow Russia so that the US can break up the BRICS alliance & further prevent anything but dollars flowing for oil, which would allow them to further tax the entire world with inflation.