That is, he wants Trump to agree that Ukraine will not be allowed in NATO and he will keep the land he's conquered.

He may also have additional demands, like that Ukraine won't be armed by America or Europe, which is probably a non-starter.

This is certainly not an agreement to a lasting peace. But peace can only happen if you can get the warring parties to stop shooting at each other and start talking. So this isn't an end to the war, but it is a necessary step if the war is to ever end.