Why does Palestine have the right to exist and Israelis do not belong in Palestine?Please ASAP and give me details

I'm not sure this question has a solid "yes" or "no."  If we use the religious book argument, the God of Abraham promised specific areas of land to both the descendants of Isaac and Ishmael.  The area we call Palestine was promised to the Hebrews, Isaac's children, not the Arabs, Ishmael's, although they were also promised vast areas.  Muhammad was born in today's Saudi Arabia, not Palestine.

If we use the argument of history, the area was lived in mostly by Arabs since AD 70 when the Romans drove out the Jews after the Jewish Revolt.  But many Jews have lived there throughout this time, also.

Another historical argument is that the Palestinians are the descendants of the ancient Philistines, the people who invaded Israel after the Hebrews drove out the Canaanites in the centuries after Moses.  This doesn't hold water, since the modern Palestinians are not related; the earlier Philistines were wiped out by the ancient Phoenicians, which is to say the Lebanese.

Then there's the idea that Palestinians are descended from the Canaanites, also not true.  Palestinians are Arabs originally from Arabia and the lands to the east.

The real problem is that the Holocaust convinced the world the Jews needed a modern nation-state, and since it is the area of ancient Israel, it was the place chosen.  Palestinians were offered equal citizenship with all the same rights as Jews, but their leaders fomented a war in the fear they would lose power over the Palestinian people.  If Palestinians had votes in a modern democratic Israel, how could their fuedalistic leaders have kept control?  But they lost the war, and their Arab brothers have bewailed their plight since 1948 but have never offered real help. The Arab nations keep them in refugee camps, and have never offered to share any of their land, have never offered any but the most parsimonious financial aid.  The hypocrisy among Arab governments about the Palestinians is appalling. The Arab people are very affected, but their governments don't seem to really care.

Personally, I believe both Israel and the Palestinians obviously have the right to exist, and that both Israel and other states such as Jordan, Syria and Saudi Arabia should all offer land for a Palestinian state, and the incredibly rich Arab countries should financially help set it up.  Any other plan is unworkable, as we have seen for the last 61 years.