You have a couple of problems here:
1. There was no country or nation known as Palestine. The area was under the British mandate after it was taken from the Ottomans. The region was labeled Palestine way back as an attempt to de-Judify it, but if you look at things like The Palestine Post, the Palestine soccer team and the stamps and currency from the mandate era you will see that the term Palestine was associated with Israel and the Jewish people.
2. As the nation of Israel was created via the mandate and voted on and ratified by the UN, claiming it was stolen from anyone is wrong.
3. As there was no nation of Palestine, there would have been no Palestinian to steal it from.
4. The Arab leadership rejected the partition plan and attacked
instead of accepting the existence of a state of Israel. It has also rejected a
variety of plans which would have given it a nation and coexistence. Israel has unilaterally given up land for the promise of peace. The Hamas
symbol still includes an image of the entire of Israel.
Those maps have been debunked repeatedly. You can read up
here if you would like. If you would like to see what happens when an Arab woman walks around in a "settlement", watch
here. Notice that Israelis aren't allowed in Arab cities.