While you are a member of an organized crime family in Bitlife, you have the option to murder your fellow mobsters via whack. To use wack, you must click on jobs and then find your mafia, click on it and then find a list of your fellow mobsters.
Once you see a list of your fellow mobsters, click on any one of them, and you will find the option wack under their profile. However, if you use wack outside of them not being a rat or accusing you of being a rat, you might annoy your mafia and get wacked yourself or kicked out.
So if you are trying to complete this week's challenge by wacking five mobsters in Bitlife, you will need to use this option called wack and be careful about using it.
We recommend waiting for someone you think is a rat or become a rat yourself and wait for someone to accuse you so you can wack them. It also helps to be higher up in the mob, such as the boss or underboss. If you are a high rank, you are less likely to face the consequences of killing underlings.
For more on Bitlife, check out both How to increase your notoriety in the Mafia in BitLife and How to join the Mob in Bitlife – Bitlife Mafia guide