Cybercrimes are named according to what exactly is being taken or damaged. Some crimes target money, some target equipment, and some specifically target a person's personal identifying information.
When someone unlawfully obtains and uses another person's personal details, such as their name, date of birth, or bank information, to pretend to be that person, this is called identity theft. The stolen identity can then be used for fraud, such as opening accounts or making purchases in the victim's name.
"Cyber bullying" involves using digital communication to harass, threaten, or humiliate someone, which is a different harm from stealing someone's identifying information. "Identity Phase" and "Cyber Know How" are not established terms in computer studies or cybersecurity, so they cannot describe this specific crime.
Match the harm described in the question, here, stealing someone's identity, directly to the term built from those exact words: identity theft.