What is the right way for Wudu? Is it true that if you pass gas that you have to make Wudu completely?

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

How to perform ablution:

First, wash your hands three times. Then rinse your mouth three times. Then sniff water up your nose and blow it out three times. Then wash your face three times. Then, wash the arms to the elbow three times. Then wipe the head slightly with water, starting with the front of the head, moving to its back and returning one's hands to the front. Then, wipe your ears. Finally, wash the feet and the heels three times. So, this is how the Prophet used to perform ablution. Some companions reported to have seen him doing the washing once. Others reported to have seen him doing it twice, and a third group reported to have seen him wash the ablution parts of the body three times. Allah knows best.
If the person is certain that he has passed gas by smelling something or hearing it or being sure of having done that, his ablution becomes null.

The evidence for this is that Abu Hurayrah narrated that the Prophet said: “Allah does not accept the prayer of a person who has released gas until he performs a new ablution.” A man from Hadhramawt asked Abu Hurayrah : “What does releasing gas mean?” Abu Hurayrah answered: “Wind with or without sound.” [Al-Bukhari and Muslim]

For more benefit on obligatory acts that must be washed in ablution, and which are detailed in sequence order, please refer to Fatwa 326854.

For more benefit on the nullifiers of ablution, please refer to Fatwa 84093.

For more benefit that doubting the nullification of Tahaarah does not nullify ablution, please refer to Fatwa 31363.

Allah knows best.