Combining two systems: Adding Inventory to Save Data

So my problem is a bit of a specific one.

I'm pretty inexperienced when it comes to programming, and I followed two separate tutorials to implement the save and inventory systems for my game: these two articles for saving and loading, and this tutorial for creating an inventory.

Both systems seem pretty good to me - my main problem is that I don't know how to feed the values from the inventory system into the save system (because, again, inexperienced).

Here's the Inventory file:

 public class Inventory : MonoBehaviour {
 
     public Image[] itemImages = new Image[numItemSlots];
     public Item[] items = new Item[numItemSlots];
     public const int numItemSlots = 16;
     public void AddItem (Item itemToAdd) {
 
         for (int i = 0; i < items.Length; i++) {
             if (items[i] == null){
                 items[i] = itemToAdd;
                 itemImages[i].sprite = itemToAdd.sprite;
                 itemImages[i].enabled = true;
                 return;
             }
 
         }
     }
 
     public void RemoveItem (Item itemToRemove)
     {
         for (int i = 0; i < items.Length; i++) {
             if (items[i] == itemToRemove) {
                 items[i] = null;
                 itemImages[i].sprite = null;
                 itemImages[i].enabled = false;
                 return;
             }
         }
     }
 }

And here's the PlayerStats:

 [System.Serializable]
 
 public class PlayerStats {
 
     public int SceneID;
     public float PlayerPosX, PlayerPosY, PlayerPosZ;
 
     public float coinage;
     public ArrayList items;      //I added this preemptively because I thought it might help - it doesn't currently serve a purpose.
 }
  

And the PlayerControl:

    public class PlayerControl : MonoBehaviour
     {
         [HideInInspector]
         public bool facingRight = true;         // For determining which way the player is currently facing.
         [HideInInspector]
     
         public float moveForce = 365f;            // Amount of force added to move the player left and right.
         public float maxSpeed = 2f;                // The fastest the player can travel in the x axis.
         public bool isSitting = false;
         public GameObject inventory;
     
         private Transform groundCheck;            // A position marking where to check if the player is grounded.
         private bool grounded = false;            // Whether or not the player is grounded.
         private Animator anim;                    // Reference to the player's animator component.
     
         private void Start()
         {
             if (GlobalControl.Instance.IsSceneBeingLoaded)
             {
                 PlayerState.Instance.localPlayerData = GlobalControl.Instance.LocalCopyofData;
                 transform.position = new Vector3(
                     GlobalControl.Instance.LocalCopyofData.PlayerPosX,
                     GlobalControl.Instance.LocalCopyofData.PlayerPosY,
                     GlobalControl.Instance.LocalCopyofData.PlayerPosZ
                     + 0.1f);
                 GlobalControl.Instance.IsSceneBeingLoaded = false;
             }
         }
        
         void Awake()
         {
             // Setting up references.
             groundCheck = transform.Find("groundCheck");
             anim = GetComponent<Animator>();
             inventory = GameObject.Find("Canvas").GetComponent<OpenInventory>().Inventory;
         }
     
     
         void Update()
         {
             if (Input.GetKeyDown(KeyCode.F5))
             {
                 PlayerState.Instance.localPlayerData.SceneID = SceneManager.GetActiveScene().buildIndex;
                 PlayerState.Instance.localPlayerData.PlayerPosX = transform.position.x;
                 PlayerState.Instance.localPlayerData.PlayerPosY = transform.position.y;
     
                 GlobalControl.Instance.SaveData();
             }
     
             if (Input.GetKeyDown(KeyCode.F9))
             {
                 GlobalControl.Instance.LoadData();
                 GlobalControl.Instance.IsSceneBeingLoaded = true;
                 int whichScene = GlobalControl.Instance.LocalCopyofData.SceneID;
     
                 SceneManager.LoadSceneAsync(whichScene);
             }
         }
     
         //[...]
     }

I realize that there's a tutorial for saving droppable items and such immediately after the first two, but because I already have an existing Inventory, I'm not exactly sure how much it applies/how much of the work would be necessary.

I feel like it's just a matter of taking the right values from Inventory and putting them in PlayerStats and PlayerControl with the right setup - plugging in the wires, so to speak. Problem is, I don't know where to start.

Can anyone help me?