This article cites a Palestinian Central Bureau of Statistics (PCBS) study that deals with the West Bank and Gaza emigration:
about 7,000 people leave the West Bank and Gaza every year, mostly for
economic opportunities rather than to escape the conflict with Israel,
according to the Palestinian Central Bureau of Statistics (PCBS).
The study was done in conjunction with MEDSTAT, a European Union
project aiding Mediterranean countries with statistical research. It
was paid for by the Palestinian Authority. Some 15,000 households were
questioned in face to face interviews, including 5,000 in the Gaza
Strip.
So, there is a way for these 7000 people/year to leave those areas, if this figure is accurate.
However, the article does not deal with how they manage to emigrate. This article dives into more details about this:
Gaza’s younger and educated population is leaving the Strip in search
of a better future in Europe while risking their lives in a dangerous
journey running through Africa’s countries.
The same article only mentions Belgium as a country that is accepting these immigrants:
(..) Belgium, where a large community of over 22,000 Gazans is rapidly forming.
(..) Obtaining the proper papers in Belgium is also a tedious process,
This confirms that Israel is not a destination country and this is also confirmed by this Quora answer that says that receiving Israeli citizenship is very rare:
It is possible, in very extreme circumstances, such as having an
Israeli spouse under certain conditions or based on particular
services to the Israeli government (and even those situations are
often contravened). However, most Palestinians cannot gain Israeli
citizenship, especially if they were born and raised outside of
Israel/Palestine.