Conducting the Pesach (Passover) Seder meal
Refraining from work on the days of Passover when work is forbidden by the Torah
Praying, and reading the Torah-portions for each day
Avoiding leavened foods (bread, etc.) during Passover, as commanded in the Torah (Exodus ch.12)
Family, friends, and the synagogue.
They,1. Clean their house2. Make sure there is no yeast in the house3. Prepare for the meal (Seder meal)
Jerusalem is a city that is sectioned into four quarters and is special in different ways to Jews, Christians, and Muslims.
Christians in Israel celebrate Christmas in ways similar to those seen in many other parts of the world. Jews in Israel by and large do not celebrate Christmas.
they celebrate
Saturday is the Sabbath in Judaism. Orthodox (and some non-orthodox) Jews will not work. Many non-Orthodox Jews will work, but still remember the Sabbath day in their own ways. (And yes, there are some Orthodox Jews that work on Saturdays, but they do not advertise this fact).
Yes. But they celebrate it in different ways based on their religion.
It isn't. Some people think that the last supper was a Passover seder, however, the timing was wrong for that to have happened.
Red Letter Days are special day with specific meaning and are usually fixed holidays. Depending on the type of day it is (Christmas, Passover, Eid, etc), the celebration is more appropriate if the activities are related to the day itself.
Some ways to celebrate Christmas in America are to give presents and decorate Christmas trees. Don't forget the ornaments, including the star!
they celebrate it in their traditonal ways
It was one of the many ways in which the Nazis humiliated the Jews.