Versions of the Kaddish are said during any of the daily worship services, including festival services like Passover, but only if there is a minyan present. A minyan is traditionally 10 jewish men, but in liberal branches of Judaism, 10 Jewish adults. (The various kaddishes serve as punctuation in the service, marking the end of each section .)
Kaddish is said every day of the year. For its phonetic recital see the attached Related Link.
You can say Kaddish for anyone you know that has died. However, if your parents are both alive, you should seek their permission.
The tradition is to say Kaddish for 11 months after the death, and then for life at Yizkor services (on Yom Kippur plus 3 times a year, once for each pilgrimage festival). You need a minyan to say Kaddish, so it's usually during the 3 daily services, but you can say the kaddish after study if you are with are a minyan worth of Jews who have studied Torah (broadly interpreted).
yes
Kaddish is said at the end (and at several points in the middle) of every prayer service. Kaddish is also often recited at the end of a Torah class or a Siyum--the completion of one of the books of the Torah. Often a bar mitzvah boy will "make" a siyum and kaddish will be recited. But just to say kaddish at the party, no.
Yes, it can be done, but if you can't travel, you can say Kaddish in your synagogue.
No, the men in the concentration camp did not remember to say the Kaddish for Akiba Drumer in the book Night by Elie Wiesel. They were consumed by their own struggle for survival and had become desensitized to the suffering of others.
how do jewish people say passover in their language
The kaddish are not a who. The Kaddish is a family of related prayers in the Jewish liturgy. Technically, these are doxologies, that is, short prayers of praise that are used to punctuate longer services, dividing or marking the ends of sections of a service. There is the long Kaddish, the short Kaddish, the Kaddish after study, and the mourner's Kaddish. The latter is a relatively short Kaddish reserved to be said by mourners (if any are present).
At least 10 - the size of a minyan.
Kaddish is written in Aramaic.
Passover is called "Pessa'h" in French. This is not a French word, but comes from Hebrew.