This is pretty vague...Are you having issues with setting up the player's name, or are you trying to event something that checks the player's name, or maybe an issue with an event like trainer(x) that needs a specific name to work properly?
Sharing info helps a lot when looking for answers!
When you say put in a certain name, do you mean when the player names their character at the start of the game, or at a certain point in the game?
When you say "add a special character", do you mean that the player character would change to a different sprite, or that a new character besides the player would appear in the game?
This might not be quite how you're wanting it, but I'd suggest asking the player for their name first and putting in a list of names that the player picks from when creating their character (with an option for "other" at the end that brings them to where they enter it in themselves). The code for the special character (Script:pbChangePlayer(2), I think) would go with the special name, and the other names would have the basic boy/girl script tagged with them. (The custom name would just pull up the usual "Are you a boy or a girl?" after the player put in their name._