Charisma Build in Fallout 4 focuses on a character whose goal is to influence NPC, wasteland creatures, and build settlements. What makes a charisma build unique is the ability to force enemy NPC to attack on your behalf and increase the effectiveness of your companions. Using a high charisma build and perks will help you craft and build settlements and general storytelling aspects of Fallout 4.
However, the damage of a Charisma build will be lower than that of others, like the Sniper and Sneak build. With high Charisma and Intelligence, you gain access to Science, Gun Nuts, Intimidation, and Local Leaders. Thus, players should pick this build if dialogue and settlement construction are their priority when playing Fallout 4.