If a Muslim does wudu and does not say Bismillah, then his wudu is valid, but he is missing out on the reward for doing this Sunnah. To be on the safe side, the Muslim should not omit saying Bismillah before wudu.

If a man kisses his wife or touches her hand or hugs her but he does not emit anything, then his wudu is not invalidated and it remains as it is. But if madhiy or maniy come out of him as a result of kissing her, then his wudu is invalidated.

How to make wudu: 1 -wash the face completely once, 2- washing the arms up to the elbows once, 3- wipe entire head including the ears, 4- wash the feet up to the ankles once.