The end game is what analysts first stated very early on in the invasion: Nakba 2.0 (ethnic cleansing).There's no endgame plan.
Or whatever the Israeli government or military have, it's pretty clear that they simply do not have the ability to fully carry out those plans (unless it is what is happening right now, in which case, their plan sucks lol).
Nakba 1.0 worked well in 1948, as nearly a million Palestinians fled/expelled. This time around, there is nowhere to expel the Palestinians.
Israel was hoping that Egypt would open the borders on humanitarian grounds, but Sisi did the exact opposite. Sisi received a lot of criticism but his point of view was absolutely spot on - that Gaza would cease to exist as a Palestinian territory if all the Gazans fled, as Israel intends.
Egypt banked on the idea that Israel would eventually cower to international pressure and stop the aggression. But Israel doesn't back down and continues to target Gazans. Hence, it is a slow genocide in the process. One thing we can be sure of now is that most of Gaza is inhospitable and deaths will continue to rise even if IDF slows it's momentum or backs up. In other words, make life so miserable that Gazans will flee voluntarily.
If Gaza falls, the Egyptian Sinai peninsula can be next and will be a lot easier since it is already demilitarized as per the 1973 peace treaty requirement.