Yes God gave the land to Abraham and the Jews in the beginning,

“And Yahweh said to Abram, after Lot had separated from him: ‘Lift your eyes now and look from the place where you are – northward, southward, eastward, and westward; for all the land which you see I give to you and your descendants forever. And I will make your descendants as the dust of the earth; so that if a man could number the dust of the earth, then your descendants could also be numbered. Arise, walk in the land through its length and its width, for I give it to you.” (Genesis 13:14-17)"

But, like anything, it came with fine print...

"“But if you do not obey Me, and do not observe all these commandments … but break My covenant … I will bring the land to desolation, and your enemies who dwell in it shall be astonished at it. I will scatter you among the nations and draw out a sword after you; your land shall be desolate and your cities waste … You shall perish among the nations, and the land of your enemies shall eat you up.” (Leviticus 26: 14, 15, 32-33, 28)"

Yes, in the Bible, Yahweh, the God of Abraham, Isaac, and Israel, told the Hebrews that the land could be theirs – if they would obey his commandments. Yet, as the Bible tells the story, the Hebrews were rebellious against Yahweh in all their generations.

“Therefore Yahweh was very angry with Israel, and removed them from His sight; there was none left but the tribe of Judah alone…. So Israel was carried away from their own land to Assyria, as it is to this day.” (2 Kings 17:18, 23)

“And I said, after [Israel] had done all these things, ‘Return to Me.’ But she did not return. And her treacherous sister Judah saw it. Then I saw that for all the causes for which backsliding Israel had committed adultery, I had put her away and given her a certificate of divorce; yet her treacherous sister Judah did not fear, but went and played the harlot also.” (Jeremiah 3: 7-8)

So yeah, God gave them the land under some conditions. But they broke them, so the land is no longer 'given to them by god'

The Israelis did give them some of their lands back but purposefully kept the Palestinians weak and their resources limited. The main part in this is water. The Israelis only allow a small amount of land to be close to the water, the Gaza Strip, which is also cut off from the rest of the West Bank. Connection to water is extremely important to help a nation thrive. It allows travel, trade, food, and other valuables for a nation. Not only is the connection to the ocean limited, but Israel's water company Mekorot restricted water supply to villages in the West Bank, in the middle of summer. Israelis weakened and hurt tens of thousands of Palestinians from deydration in the harsh dessert. This helps some parts of the West Bank to be controled and prevent the Palestinians from fighting.