No one is sure that God exist why do the worship them?

Answer 1

What is someone who believes God exists and someone who does not believe in God? :

They may believe in him because of the making of The Bible, Which was wrote by God himself. If you are an Atheist, you do not believe in the existence of God, more specifically, Jehovah. Jehovah is the God you believe in when it comes to the Christian religion. The opposite of an Atheist, A Christian believes in God (Jehovah) as their savior, the creator of earth, And also creator and father of all people. In the Bible, it is said that the people who follow in the footsteps of God go to heaven, a place where "good" people go when they die, it is filled with peace and no disturbances whatsoever. It is also said that people that make it to heaven will have eternal life, meaning that someday when god comes back down to earth, all his people will be able to live again. People who disobey the commands of God shall go to Hell after dieing, a place that is said to be below the earths core, where it is hot, and filled with flames and embers. The ruler of Hell is Satan, (Like god is to heaven) otherwise known as the Devil. The Devil is a fallen angel of God, which means he did not do the bidding of Jehovah. Though you can go one way or the other, God is known for being able to forgive people for their sins. Sins are when you do something that is against the bible. Atheists believe in none of the following because they do not believe in Jehovah as a Christian would.

Does God exist?

It is up to the individuals own beliefs of deciding whether God does or does not exist.

Why do the ones that do believe in him (also known as Christians) worship him?

Because they believe that Jehovah has the power to heal, control what goes on within a persons life and guide them into the direction of Christianity. They want to be in presence with him when they meet him in heaven.