Selection Screen

How do you make a screen where you cna select stuff? An example is like in FMVH when you use the teleporting pads it opens up a menu asking where you wanna go. Also in Evolution maps when you reach a certain level a menu pops up asking what you want to evovle to. I wanna do something like this, so could anyone tell me the triggers?

use the dialog triggers. create a dialog variable. then create dialog buttons for that dialog. set them all as variables. then create triggers with the event "dialog button clicked" and the condition "clicked button = button variable" and then whatever actions that should take place.