I searched quite a lot and couldn't find any evidence of a coordinated approach to Arabs being told to flee, although there was certainly some towns / villages that were told this and there's Palestinian witnesses who can be found telling their stories online.
What happened is pretty obvious factually because there's historical evidence that supports it.
The Jewish people were trying to establish independence in Israel and the Arab people didn't want them to.
The first serious proposal for sharing the land was made in the 1930s and that was rejected by the Arabs even though it gave them 80% almost all of which had no Arabs living on it.
In fairness, I don't actually blame them for that. They had just suffered a humiliating loss of their empire and had a foreign non-Muslim government arrive and tell them what to do and they reacted angrily at it as potentially most people would have done.
Add into that, for 600 years their empire had ruled the whole region, and their culture was based significantly on the ideology that Muslims were superior to others, something that were not accustomed to having challenged. They had been superior by law to Jews and others, who were their "dhimmi"- much in the way white people would have felt superior to Black people in old Alabama - it was deeply ingrained.
It wasn't possible in their collective psyche for them to say "well the Jews were here first and we did take their land originally so maybe it's fair if they have a little of it for their own" because that was completely against their entire ideology of life. So they revolted very violently to it, beset on the idea that absolutely no Jewish sovereignty could ever be accepted on land that in their minds was "Muslim" owned.
At the same time, there was a small number of Jews in the zionist movement, who had been trying for a long time to get Jewish statehood for a variety of very fair reasons. Some also saw Israel as their ancestral home, for which in fairness their is a very solid set of historical supporting evidence.
There was a greater number of Jews who were not really political or "zionists" but were left with largely fuck all choice, because they had been persecuted and exterminated almost entirely in Europe and then persecuted pretty horrifically in their homes around the middle east too. So whatever way the cake was sliced, they had to have somewhere to live.
Had Arabs not persecuted Jews around the MENA region in the 40s and 50s I am honestly not sure Israel would have taken off, as most people would prefer not to leave their homes, businesses and possessions and flee somewhere with nothing but if you are backed into a corner, what are you supposed to do? They knew what happened in Germany so they understandably sought safety.
Moreover, I'd imagine there was a shift in the collective Jewish psyche where they saw Nazi antisemitism and it's consequences in Europe, and then saw similar spreading like wildfire around their homes in the middle east and I'd guess many just came to a point of realising independence was probably their only chance for safety, given how unhinged the world seems to become around Jews.
So I have empathy for both sides here. But what is certainly true is that Israel / the Jews didn't set out to expel Arabs or anyone else. But there were circumstances that made peaceful coexistence impossible.
Violence towards Jews had been ongoing for decades. People often cite the Jewish terrorism that began much later on, but for 18 years prior to that, there had been more than 60 Arab terror attacks against Jews - some were horrifically brutal and if you do that for 18 years I do think it means peaceful coexistence becomes very hard.
When the state of Israel became a reality, there was a war. A civil war was started in 1947 after the UN declaration, and over that time there was very violent fighting on both sides. Both sides were trying to expel each other. And then once Israel announced it's statehood the civil war turned into an international one - 5 Arab Armies vs Israel.
I think people forget the Jews did at least try peace. Not least because I imagine they thoroughly expected to not survive an Araba attack. The quote I always remember is this one:
"We appeal – in the very midst of the onslaught launched against us now for months – to the Arab inhabitants of the State of Israel to preserve peace and participate in the building of the State on the basis of full and equal citizenship and due representation in all its provisional and permanent institutions."
This comes from the Israeli Declaration of Independence, proclaimed on May 14, 1948. It was read aloud by Ben-Gurion. And it reflects the collective stance of the provisional government, which was a stark contrast to the Arab one which was promising a war of annihilation. The Arabs invaded 4 hours later, I believe.
I think the truth of the matter is what I have said above, and while I do not see any evidence to support that Palestinians were told en masse to evacuate, what I do think is true is that...
Some were told to evacuate - probably isolated groups
Wealthy Arabs moved as soon as any war started because it just wasn't safe
Many left out of fear
Many left because they didn't want to be ruled by Jews
Many left because they were forcibly displaced.
It's important to understand all of this in the context of war, not as a deliberate planned policy to expel people. The Nakba was a tragic outcome, but it occurred during a violent conflict. By contrast, the Jews who were expelled or driven out of Arab countries weren’t at war with those nations. They were targeted solely because they were Jewish. In my view, there’s no moral equivalency here - the expulsion of Jews from across the Middle East was a far greater injustice because there was no conflict involved.
What’s often overlooked is that, in the years that followed, Israel - despite relentless hostility and threat from the Arab and Muslim world - made a real effort to create a state that offered a home to both Jews and Muslims. And it did this more successfully than any other regional government has managed. They get no credit for that.
What I find most disappointing is when people are so blinded by anti-Israel bias that they cast Jews as the villains of the story, without any grasp of the full historical context that really in 1948 probably nobody was a villain.
The Jewish aspiration for statehood was entirely reasonable. There is overwhelming historical, religious, and cultural evidence of their deep and continuous connection to the land. Their holiest sites are there. They were indigenous to the region. And after millennia of persecution - culminating in the near-destruction of European Jewry - they had every justification to seek the same rights to independence and security as any other people.
They did not, and had never had the option to live freely, safely and equally in their lands when ruled by Muslims - that was already proven and was never, ever, ever offered to them.
Of course, this wasn’t fair to every Palestinian. But it also wasn’t fair to every Jew, every Christian, or every one of the millions of displaced and wronged people across the world in the 20th century.
What matters is that the cause of Jewish statehood was justified, morally sound, and a far more balanced outcome than allowing the entire Middle East to be claimed exclusively by Arab states while Jews were left with nowhere at all.
People just have to come to that and settle on making peace.