Heath regain via Pickup code halp me

So I am trying to develop a pickup script but nothing I do seems to be working. I get a boatload of errors and everything I do to fix it seems to have that close but no cigar thing going for it. the code is in c# and it uses two scripts to execute one to manage player heath and the other exists to destroy the game object depending on whether or not the player is at full health. Note that 90% of this code is reverse engineered from various parts of the survival shooter unity project.

I beleive the second code is bug free

first code named PlayerHealth

 using UnityEngine;
 using UnityEngine.UI;
 using System.Collections;
 
 public class PlayerHealth : MonoBehaviour
 {
     public int startingHealth = 100;
     public int currentHealth;
     public Slider healthSlider;
     public Image damageImage;
     public AudioClip deathClip;
     public float flashSpeed = 5f;
     public Color flashColour = new Color(1f, 0f, 0f, 0.1f);
 
 
 
    
     AudioSource playerAudio;
     PlayerShooting playerShooting;
     bool isDead;
     bool damaged;
     bool AtFullHealth;
     bool Regain;
     CapsuleCollider CapsuleCollider;
 
 
     void Awake ()
     {
        
         playerAudio = GetComponent <AudioSource> ();
         playerShooting = GetComponentInChildren <PlayerShooting> ();
         currentHealth = startingHealth;
         CapsuleCollider = GetComponent <CapsuleCollider> ();
     
     }
 
 
     void Update ()
     {
         if(damaged)
         {
             damageImage.color = flashColour;
         }
         else
         {
             damageImage.color = Color.Lerp (damageImage.color, Color.clear, flashSpeed * Time.deltaTime);
         }
         damaged = false;
     }
 
 
 
     void OnCollisionEnter(Collider other)
     {
             if(other.gameObject.tag == "FirstAid")
         {
                 CapsuleCollider.isTrigger = true;
                 Regain = true;
                 currentHealth += 25;
                 healthSlider.value = currentHealth;
 
         }
     
         if(currentHealth >= 100 && !AtFullHealth)
         {
             IsAtFullHealth ();
         }
     }
 
     void IsAtFullHealth ()
     {
         AtFullHealth = true;
 
         Regain = false;
     }
 
     public void TakeDamage (int amount)
     {
         damaged = true;
 
         currentHealth -= amount;
 
         healthSlider.value = currentHealth;
 
         playerAudio.Play ();
 
         if(currentHealth <= 0 && !isDead)
         {
             Death ();
         }
     }
 
 
     void Death ()
     {
         isDead = true;
 
         playerShooting.DisableEffects ();
             
 
         playerAudio.clip = deathClip;
         playerAudio.Play ();
 
             playerShooting.enabled = false;
 
         Application.LoadLevel ("LoseScene");
     }
 
 }
 

second code begins here

 using UnityEngine;
 using System.Collections;
 
 public class HealthUp : MonoBehaviour 
 {
 
     GameObject player;
     bool PickedUp; 
     PlayerHealth playerHealth;
     BoxCollider BoxCollider;
  
     void Awake ()
     
     {
         player = GameObject.FindGameObjectWithTag ("Player");
         BoxCollider = GetComponent <BoxCollider> ();
         playerHealth = player.GetComponent <PlayerHealth> (); 
      }
     
     void OnTriggerEnter (Collider other)
     {
         if(other.gameObject == player)
 
             if (playerHealth.currentHealth <= 100)
 
                 {
 
                     
                     
                     BoxCollider.isTrigger = true;
                     Destroy (gameObject);
                 }
 
     }
 }