Gaza has a population of 2.3 million people living on a 23 km long x 7-12km wide stretch of land, in the desert. They don't produce nearly enough to feed and maintain that population, so they are at the mercy of donations and aid in order to survive. You're allowed to travel, but can only do so with the permission of the state of Israel.
"In February 2016, Israel implemented a new policy allowing any Gazan, for the first time in 20 years, to go via Israel to Jordan in order to travel abroad. However, the new policy came with a stiff requirement: Gazans must commit to not return to Gaza via Israel for at least 12 months."
https://www.hrw.org/news/2022/06/14/...-air-prison-15
And that is IF the state of Israel even allows you to leave, which in most of the cases they receive, they just ignore. And if you are allowed to leave, who knows what happens (arbitrary interrogations, torture are not uncommon by the IDF).
https://www.hrw.org/reports/pdfs/i/israel/israel946.pdf
So basically, if you're a person who is born in Gaza, your options for a better life are really shite. It's not a concentration camp of course... that is implied exaggeration for a literary purpose of effect, but let's just say the place is more akin to an open air prison for the 2 million people inhabiting the place.
"Moreover, figures published by the Palestinian Central Bureau of Statistics (PCBS) indicate that the poverty rate in the Strip has reached 53 percent, with one-third (33.7 percent) of Gaza residents living in extreme poverty."
https://reliefweb.int/report/occupie...reme%20poverty.