Palestinians don't have a country, Ukrainian can still have a sovereign state.
Your comparison do not make sense.
No you can't. When "peace" with an invader is predicated on giving up your right to self-determination (in this case an imposed neutrality) and giving up your own land to that invader, true sovereignty no longer exists.
Where? Isreal control their borders. There is no Palestinian State. There is an Ukrainian state.
Ukraine is still sovereign on the major part of its territory.
Your comparison do not make sense. Lebanon would be a better comparison, and over there hezbollah accepted the cease fire.
"Well, Russia just annexed Crimea, they're still sovereign in the unseized territories."
"Well, Russia just annexed Donetsk, they're still sovereign in the rest of the unseized territories."
Well, Russia just annexed Luhansk, they're still sovereign in the remaining unseized territories."
Well, Russia just annexed Kyiv...........