Condition in a while loop not updated on my mkr1010
while (buttonState != LOW){
    // turn LED on:
    digitalWrite(ledPin, HIGH);
     WiFiDrv::digitalWrite(25, 255); // for full brightness
     Serial.println(buttonState);
  } 


You never update the value of buttonState in this while loop.  If buttonState is not LOW to get into the while loop, nothing inside the while loop will ever change it so every time it gets checked it will still not be LOW.  It's not going to surmise that you meant to read a pin just because you used that variable to read a pin once before.  

But do you really need this while loop?  Couldn't you just write the led pin low when you first get a press and then write it high when it first gets released?  See the "State Change Example".  Let the loop function be the loop.  It will lead to better code.  You don't see this now because you are a novice, but you are about to paint yourself into a corner with this approach and you'll soon be rewriting the whole thing.  It's a trap that gets most new coders.  Better to get it right now.