C# Script Crashes

Hi There,

I was about to write my first c# script, as i recognized, that it crashes, as soon as i execute it. Thea Idea is, to create a lockpicking system, that is kind of similar to the one from Gothic II ;) (Left / Right Key Input). Did i miss something or is there a logic issue, that i didn't noticed?

     public class Lockpicking : MonoBehaviour
     {
         public Animator lock_anim;
         public AudioSource audiosource;
     
         public Transform spawnpos;
         public GameObject ui_success;
         public GameObject ui_failure;
         public GameObject player;
     
         public Random rnd = new Random();
     
         public AudioClip lock_success;
         public AudioClip lock_failure;
         public AudioClip lock_fatal_failure;
     
         //Amount of successful clicks until opening
         public int lock_level;
     
         // Start is called before the first frame update
         void Start()
         {
             lock_anim = GetComponent<Animator>();
             audiosource = GetComponent<AudioSource>();
     
         }
     
         // Update is called once per frame
         void OnTriggerEnter()
         {
             if (Input.GetKeyDown("e"))
             {
                 lock_anim.Play("Lockpicking");
                 player.GetComponent<Animator>().Play("Lockpicking");
                 Picking();
             }
         }
     
         void OnTriggerStay()
         {
             if (Input.GetKeyDown("e"))
             {
                 lock_anim.Play("Lockpicking");
                 player.GetComponent<Animator>().Play("Lockpicking");
                 Picking();
             }
         }
     
         public void Picking()
         {
             while (lock_level >= 0)
             {
                 int correct_pick = 0; //Need to be generated random (0,1)
     
                 if (Input.GetKeyDown("a"))
                 {
                     int current_pick = 0;
                     if (current_pick == correct_pick)
                     {
                         audiosource.PlayOneShot(lock_success, 1);
                         Instantiate(ui_success, spawnpos.position, spawnpos.rotation); //create Pick Object ("...Das hörte sich gut an...")
                         lock_level = -1;
                         return;
                     }
                     else
                     {
                         audiosource.PlayOneShot(lock_failure, 1);
                         Instantiate(ui_failure, spawnpos.position, spawnpos.rotation); //create Pick Object ("...Mist, nochmal von vorne...")
                         return;
                     }
                 }
                 if (Input.GetKeyDown("d"))
                 {
                     int current_pick = 1;
                     if (current_pick == correct_pick)
                     {
                         audiosource.PlayOneShot(lock_success, 1);
                         Instantiate(ui_success, spawnpos.position, spawnpos.rotation); //create Pick Object ("...Das hörte sich gut an...")
                         lock_level = -1;
                         return;
                     }
                     else
                     {
                         audiosource.PlayOneShot(lock_failure, 1);
                         Instantiate(ui_failure, spawnpos.position, spawnpos.rotation); //create Pick Object ("...Mist, nochmal von vorne...")
                         return;
                     }
     
                 }
     
                 gameObject.GetComponent<Animation>().Play("ChestAnim");
             }
     
             return;
         }
     }

PS: Is there a way to translate (change) the name of the public items inside the editor (lock_success = Lock Success)?*

Looking forward for replies!! -Toha