We celebrate this by going to mass reacting out the last supper and getting our feet washed by the parish priest.
Roman Catholics celebrate the Mass of the Last Supper.
Holy Thursday, Good Friday, Holy Saturday - also known as the Triduum. It begins with Mass on Holy Thursday and ends with the beginning of Mass on Holy Saturday.
There are no "holy" months, but Catholics celebrate Lent.
Lent ends in the afternoon/evening right as the Mass of the Lord's Supper on Holy Thursday begins. That Mass begins the Easter Triduum which is the shortest season of the Liturgical year and comprises Holy Thursday evening, Good Friday, and Holy Saturday up until the start of the Easter Vigil.
The day before Good Friday
Yes, Catholics bury their dead during Lent except during Holy Week after Holy Thursday until after Easter Sunday.
The last supper
No, the Mass is celebrated every day.
Yes, Holy Thursday is the prescribed day for the Chrism Mass in the morning that the Bishop holds with all his priests, although it is often moved to an early day in Holy Week. And then in the evening is the Mass of the Lord's Supper.
Passover is a Jewish tradition, not Catholic. Catholics observe Holy Thursday, the Mass of the Last Supper.
The Catholic Church says Catholics should not eat meat on Ash Wednesday and all Fridays during the holy season of Lent. Thursdays (including Holy Thursday- the Thursday before Easter Sunday) are not part of the no meat rule. I'm not sure about other religions, only Catholicism.
Primarily Catholics celebrate Sunday by assisting at Mass.