welcome to the board. In answer to your questions:
1.Sacred Writings - they believe the bible is sacred but have hundreds of books published which are supposed to help one understand the bible.
2.Holidays and Rituels (dates if possible) They don't allow celebration of the following - Christmas, Easter, Birthdays, valentines, Any Saints days, Thanks Giving, Harvest Festival, Mothers Day, Fathers Day, Bonfire Night, Independence Day and anything else you can think of.
They do celebrate wedding anniversaries and Jesus dying.
3.Where do Jehovah's Witnesses meet to perfrom religious ceremonies.
They don;t really have ceremonies - but they do insist you meet up to study their publications and learn how to preach from door to door at 5 weekly meetings.
4.Who is the god?
Jehovah
5.What do you think about life after death?
I personally don;t believe in life after death. JW's believe that very soon there will be a war on earth called Armageddon in which everyone who is not a baptised Jehovah's Witness will be slaughtered. All those who are JWs will survive and after they have cleaned up the bodies with the help of crows will live forever in a paradise earth.
Hope this helps - maybe you can let me know why you are asking?