unity how to call function when key is held down and stop when key is not held down code example

Example 1: how to see if they are aholding down a key unity

input.GetKey("Key")

Example 2: How to hold key down unity

// If Key Is Held Down
Input.GetKey("Key")

// If Key Is Held Down With if Statement
if (Input.GetKey("Key"))
{
    // Whatever is in this will get called when "Key" is held down
}

// Example 
if (Input.GetKey("left shift"))
{
    RunBool = true;
    WalkBool = false;
}

Example 3: how to check if key is held in unity

float startTime; // declare this outside any function
 
   void Update () {
     if (Input.Get$$anonymous$$eyDown("w")||Input.Get$$anonymous$$eyDown("s")){
       // key pressed: save the current time
       startTime = Time.time;
     }
     if (Input.Get$$anonymous$$eyUp("w")||Input.Get$$anonymous$$eyDown("s")){
       // key released: measure the time
       float timePressed = Time.time - startTime;
       // do here whatever you want with timePressed
     }
     RandNum = Random.Range(1, 1000);
     if (Input.Get$$anonymous$$eyDown($$anonymous$$eyCode.W) || Input.Get$$anonymous$$eyDown($$anonymous$$eyCode.S)){
       if(RandNum > 1){    
         if(RandNum < 1000){
           inBattle ();
         }
       }
     }
   }