Can hypnosis help you to forget certain memories for a lifetime?
I don't know much about hypnosis but according to the articles I read this on Wikipedia
During hypnosis, a person is said to have heightened focus and concentration. The person can concentrate intensely on a specific thought or memory, while blocking out sources of distraction.
Hypnotised subjects are said to show an increased response to suggestions.
Hypnosis is usually induced by a procedure known as a hypnotic induction involving a series of preliminary instructions and suggestion. The use of hypnotism for therapeutic purposes is referred to as "hypnotherapy", while its use as a form of entertainment for an audience is known as "stage hypnosis". Stage hypnosis is often performed by mentalists practicing the art form of mentalism.
This should give you the idea that memories can be forgotten but can't be deleted.
But the scientists have already found a way to erase memories,
There are many reasons that research is being done on the selective removal of memories. Potential patients for this research include patients suffering from psychiatric disorders such as post traumatic stress disorder, or substance use disorder, among others.
Memory erasure has been shown to be possible in some experimental conditions; some of the techniques currently being investigated are: drug-induced amnesia, selective memory suppression, destruction of neurons, interruption of memory, reconsolidation,and the disruption of specific molecular mechanisms.
Though hypnosis helps us forget the memory but it will remain in our brain forever until something reminds us of it again.