How do I call a function when my slider is at max value?

Hello everyone, I have a horizontal sider that goes from 0-100. It's supposed to start at a random number and then increase to 100. My code is:

 void start(){
 charOneWait.GetComponent<Slider>().value = Random.Range(0, 100);
 }
 
 void FixedUpdate () {        
 charOneWait.GetComponent<Slider>().value += Time.deltaTime * 9;
 }

My problem is I need an event to happen when the slider is at it's max value and I'm not sure where I should call that function. I can't call it in Start() because it needs to wait until the slider reaches 100. I can't call the function in update() or fixedupdate() because then the event is being called more than once.

Thanks in advance!