Thanks for the answers Lal.
How about the sankhara that is involved while doing Anapana. If ALL sankhara(SABBE sankhara) leads to dukkha, how can Anapana sankhara lead to dukkha when it helps end the rebirth process thus helps end suffering?
Even though it says ALL sankhara lead to dukkha, Anapana sankhara seems to be an exception.