Its not about stopping the fighting its about sitting down and making a deal, yes you sacrifice territory but stop the war, stop the killing and of course safety guarantees that Russia can't possibly ever wage war on Ukraine in the future, problem solved.Unlike the Russians, the Ukrainians are not fighting a war of conquest. If Russia stops fighting, Russia remains. If Ukraine stops fighting, Ukraine disappears.
There is also the small matter of whether the people of Ukraine would prefer to live under totalitarianism or to live under democracy. With family connections in Ukraine but less than in 2022 (one, a civilian, died after the Russians occupied aouthern Kherson), I am certain that most people in Ukraine would hate to live in a state governed by Russia. Some would rather die fighting. Some do.