Is it permissible to make ghusl/have a bath while fasting? How should one sniff water into his nostrils and gargle?

The following is stated in the religious resources: "A person who is not fasting should exaggerate while sniffing water into his nostrils and gargle to make water reach his throat." How can they be made while fasting? If water reaches the throat while sniffing water into nostrils and gargling, fasting will be invalidated.

Dear Brother / Sister,

Having a wet dream does not invalidate fasting. However, it is not permissible to remain junub so long as to miss a daily prayer. Therefore, it becomes necessary to make ghusl even if a person is fasting. Such a person does not gargle when he washes his mouth. He only rinses his mouth.  

When a deed of worship is explained, its best form is described. However, when it is related to another deed of worship, it is necessary to act accordingly. The ghusl and wudu of a fasting person is one of them.

Having a bath, having a shower and swimming do not invalidate fasting. However, it is necessary not to take water into mouth carelessly and not to swallow water. According to narrations, the Prophet (pbuh) made ghusl/had a bath when he was fasting.  

Rinsing the mouth does not invalidate fasting. If the water put into the mouth is swallowed, fasting is invalidated. When a person who is fasting washes his mouth and nostrils, he should be careful to prevent water from going down the throat. He should put water into his mouth and nose in a way that will not go down the throat.   If water goes down the throat by mistake, fasting is invalidated; it becomes necessary to perform it again as qada (one day), not as kaffarah (61 days).

Questions on Islam