How to add a hitman type thing

So I want something that's a mix of Lifesteal Assassin's and Limited Life. Basically I want 3 roles. Player, assassin, and hitman. Rn I'm focusing on hitman. but basically I want to know how to add a "You Are.." type thing and then "The Hitman." Then I want it to show sumn similar to the image that I sent, does any1 know how I would do that? (there's /title but I'm asking more about the timer)