How would I create a decrease timer function used in this video?

[Leomerya12]

Stop and clear the timer unreal engine4

Use the timer reference variable to clear and / or invalidate it: [311039-annotation-2020-08-23-104535.jpg] Check out other things that timer can do while you’re at it: [311040-annotation-2020-08-23-104623.jpg] The Set Timer by Event node is yet another alternative which may be preferable to Timer by Function as it’s not prone to typos.

Cancel the timer and then reset it.