How do I repeat a countdown infinitely?

I’m trying to make a feature in my game where the player will change character after a certain time limit is up.
I have four characters and am trying to get the player to loop between these four after the limit is up.
Is there a way I could make a countdown that, when finished, switches character and restarts the delay?
Thanks for any help!

i know that action rpg have countdown feature, 60sec for a round. u can take look.

image

Trigger an event every 10s.

Thanks for the fast reply! That helped!