During passover it really depends how religious the family is. Traditionally, you eat matzoh, a piece of lamb still on the bone, bitter herbs, Charoset (a spread made from apples, cinnamon and nuts), horseradish, and anything that doesn't have yeast or any leavening agents in them. These are only the basics, but a passover seder can have kosher cake, fruits, veggies, soup, meat, anything so long as it follows the rule of no "Chametz" which means nothing that rises. Also no beer is allowed and most carbs are out of the question because of the leavening agents in them.
Certain foods, notably pork, shellfish and almost all insects are forbidden; meat and dairy may not be combined and meat must be ritually slaughtered and salted to remove all traces of blood. Observant Jews will eat only meat or poultry that is certified kosher.
This no longer applies, since gentiles can eat kosher foods, too.
There is no food that I am aware of that only Jews eat.
No! Jews also pray and sing.
Passover is usually only celebrated by Jews
Killing and/or eating lamb during passover is actually not done by Ashkenazi Jewish custom. Many Sephardim do eat lamb during Passover with some Ashkenazi Jews starting to eat lamb too. Due to the religious laws surrounding kosher slaughter, not anyone can slaughter an animal for consumption. Specially trained people called a Shochet are the only ones allowed to do kosher slaughter.
Some kosher restaurants are open for Passover.
Generally, most scones are not allowed to be eaten during Passover because they are typically made with regular flour or cake flour. However, if the scones were especially baked with only Kosher for Passover ingredients (like matzoh cake flour or coconut flour), a Jew may eat those scones during Passover.
Only if it's certified kosher for Passover.
There are songs that are sung at the sederim. There is no tradition of lighting candles though. The only time candles are lit during Pesach is during Shabbat (the Sabbath).
There is only one country which would consider Passover to be a national celebration, and that is Israel. However, there are many other countries in which Jews celebrate Passover.
Reform Jews have only 1 seder instead of 2.
One of the great Jewish theologians of the early 20th century, Franz Rosenzweig, arranged the 3 great Jewish festivals in a triangle. He identified Passover with the creation of the Jewish people, Shavuot (the Feast of Weeks or Pentecost) with God's revelation to the Jewish people, and Succot (the fall Feast of Booths) with God's redemption of the Jewish people.Of course, each of the festivals has elements of creation, revelation and redemption built into it. Passover celebrates the exodus of the Jews from Egypt. Prior to the exodus, God was revealed only to a few individuals. With the miracles of the exodus, God was revealed to the whole people. And those miracles redeemed the people from slavery. Passover remembers all of this. The liturgy of the Passover seder re-enacts the exodus so that each Jew can feel that he (or she) was there and was personally redeemed.
No, the feast days remain the same date from year to year. Only the lenten season, Holy Week and Easter season change as they are based on the Jewish Passover.
In Israel, the Seder is on the first night of Passover. Outside Israel, Orthodox and some Conservative Jews celebrate Seders on the first two nights of Passover. Most other Jews have a Seder on only the first night, though some may also have Seders on the first two nights of Passover.
Sephardi Jews use peanuts and peanut oil on Passover, provided that it isn't otherwise non-kosher. Ashkenazim (Jews of European descent) may theoretically do so, but since some of them have the custom not to, it is rare to find peanut oil with kosher for Passover certification.