Does john leneon believe in god?

I'll assume you meant John Lennon.

The quick answer is that there has been much debate on the topic and it's pretty much unknown what he was at the time of his death, he may have been agnostic.

The longer answer is that if you listen to his songs it's fairly clear that he didn't subscribe to any particular religion, preferring instead to take spirituality as a whole and take part in different beliefs as and when he felt the need (i.e. When the band visited the Maharishi Mahesh in India). If you listen to the song Imagine inparticular it becomes strikingly obvious that he did not like the affects of religions on the world:

'Imagine there's no heaven

It's easy if you try

No hell below us

Above us only sky

Imagine all the people

Living for today...'