Can parents advice is there any such thing as repeat PSLE if the result is not good. eg if the child gets into NT but want to repeat and try one more year.

Yes. But i will not recommend to repeat primary school. You can actually let them proceed to secondary school even if they are in normal technical and during secondary school if they do well they are still able to go to express. I do have friends from normal technical jump up to express or Normal academic. Let them proceed next level instead of repeating. Thats what i will do