What do buddist believe in?
It would take days to explain, really.
If you really want to know, you should do some research, but I'll try to sum it up for you.
Everything in life revolves around suffering.
When you love someone and lose them - you suffer
When you have a possession that you cherish and it is lost - you suffer
Naturally, the way to stop suffering is to get rid of all desire - if you love nothing, you can miss nothing when it's gone.
The way to end suffering is to follow the guidelines of the eightfold path:
By following the path, you can break the cycle of rebirth and become enlightened. An enlightened person attains Buddha-hood upon death
The meaning of life is to suffer, but suffering can cease when attachment to desire ends.
Life-energy is eternal, but life is impermanent. We seek to attain Buddha-hood by reaching enlightenment.
The path that leads us to enlightenment is the eightfold path.