We are not at war with Russia, so why would we need a peace agreement? OK, let's say we give Putin Ukraine and Alaska in a "peace agreement", do you really believe he will stop? It did not work with Hitler, why would it work with Putin?
You think Ukraine can conquer Russia? The reason we want to support Ukraine is so we do not have to fight ourselves. Putin is running out of countries to invade that are not NATO. If he attacks a NATO country, there is a real chance he will lose badly. He would probably be "conquered." At that point, he would try to use nuclear weapons.
By allowing Ukrainians to fight for their own freedom, we are avoiding war ourselves, helping the Ukrainians, and avoiding a nuclear war.
trump is making threats against political rivals, which does not indicate winning.