Can a person in hypnosis, be hypnotized to forget everything that happened them, hypnosis session?

No, people cannot be hypnotized to forget everything that happened during a hypnosis session. Hypnosis does not erase memory, and any suggestions given during hypnosis are not necessarily acted upon or retained after the session. Furthermore, ethical guidelines for hypnosis practices generally prohibit the use of hypnosis to create false memories or to alter someone's memories against their will.