If it's the deal that's been speculated on for weeks now and if Israel agreed to it as Trump said, it would be about implementing the next phases of the previous ceasefire deal, the ones to do with the governance of Gaza post war and post the next rounds of a 60 day ceasefire. Under this model, Hamas will disband and disarm, and Egypt, Qatar, and potentially the UAE and Jordan will take over governance of the Gaza strip, with emigration from Gaza to other nations being a possibility for those that take up the offer. (That's the "official" line of reasoning). The so called "second and third phases" of the previous ceasefire, which were never detailed, especially on long term governance. The problem last time round was that Egypt and Qatar were not willing to play as active a role as the USA wanted, which ultimately led to the collapse of the deal as Israel resumed airstrikes on Gaza as the US begun airstrikes on Yemen, as it became more clear that the deal was not progressing, Israel was unwilling to give up further leverage. Hamas unwilling to hand over governance once it became clear that was intended.
I think Hamas might shock us all and agree to the deal if they can get safe passage for their surviving leadership to Qatar. This is a possibility. Israel with the GHF and supporting other armed groups in Gaza are laying the groundwork for a post UN and post Hamas ran Gaza.
While I'm not great on politically why such a move will be considered, militarily there is a possible reason. What makes this round of Israel invading Gaza (Operation Gideon's Chariots as Israel calls it, operation final round of genocide is more apt) different from the previous rounds is that Israel is actually sending in IDF soldiers and special forces into the underground tunnels, to try clear them out and then blow the up from the inside out. Senior IDF members confirmed this at the start of Gideon's Chariots, and recent videos have emerged of tunnels being blown up by engineering teams. Without the tunnels, and with Israel operating in 70-75% of the land area of Gaza currently (according to the evacuation notices), it becomes very difficult to even conduct the limited guerilla style operations Hamas has done over the past few months. Moving through Gaza above ground, when Israel has air supremacy from 0ft upwards, with only an occasional quadcopter drone getting shot down, is an enormous challenge.