A 'wait' action just waits. It is a pause between FSMs. if you want a timer, there are actions for timers on this site. You'll need to create a timer, have it countdown using a variable, convert to string and display on screen (UI text. You'll need to set up a canvas). Several steps. This is a common request and you can find it on this site.
I did include a screenshot of the 'countdown timer' action and the convert actions. The picture shows a countdown from '3'. At '2' it exits so it can play a sound of a guy saying '2'. (I actually have 3 of these in different states to have an announcer countdown). You can use this as a template for a timer.
Action is included as well.
