Basically I’m making a game and i want my variable to contain a dollar sign in front of the number that the variable displays on the variable, is this possible? Thanks

Yes, just have two variables. One with the dollar sign and one without. Like this:

set [money v] to [10.00]
set [money display v] to (join [$] (money))

You could use

(join [$] [money])

change money to var

You have one variable that stores the amount of money. It will be the actual number being changed in the code when you, let's say, buy something, or get more money.

The other variable just serves as a display. It just shows the user how much money they have. Every frame, you can set the display money to the regular amount of money with a dollar sign every frame with this script:

when gf clicked
forever
set [display money v] to (join [$] (money))
wait (0) seconds :: grey // may not be needed
end

Where the display money variable is shown, and the money variable is hidden. This will repeat every frame.