Is it a good idea to take chamomile tea for constipation?

It won't do much: Other than provide a bit of fluids. Fluids themselves are important. Try prune juice.

Not very effective: Camomile tea is not a very effective treatment for constipation. If you want to use some sort of tea, the best option is senna tea - senna is a plant alkaloid that softens the stool and 'irritates' the colon a bit making it contract.