how to check if key is held in unity

input.GetKey("Key")

   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 ();
         }
       }
     }
   }

/*the other guys is right it is just*/
input.GetKey("Key") /*eg - Keycode.W/A/S/D*/