Create Spells through classes in custom editor?

Hi All

I'm trying to create a spellbook through a custom editor and having little success so far.

I have a class ASpell which contains the properties within each spell and a dictionary of spells to store all these. So far I've managed to create a very basic custom editor where I can populate the list though have no idea how to ensure these aren't wiped when the game is launched.

I've looked at SerializeField, System.Serialize, ScriptableObject but I can't manage to solve this, what I'd like to think, trivial problem.

If someone could give me some pointers for what I'd need in the SpellBook class script and SpellBookEditor class script, where I need to place Serialize or whatever else I need and how to create more than one of these (if necessary) without a new overwriting everything I've done to an old dictionary.

ASpell.cs

 public class ASpell {
    public string _name;
    public int _level;
 
    public ASpell(string name, int level){
       _name = name;
       _level = level;
 
    }
 }

SpellBook.cs

 public class SpellBook : MonoBehaviour {
    public Dictionary<string, ASpell> spells = new Dictionary<string, ASpell>();

    public void Add(string name){
       ASpell spell = new ASpell(name, 1);
       spells.Add(name, spell);
    }
 }

SpellBookEditor.cs

 [CustomEditor(typeof(SpellBook))]
 public class SpellBookEditor : Editor {
    private SpellBook sb;
 
    void OnEnable(){
       sb = (SpellBook)target;
    }
 
    public override void OnInspectorGUI(){
       foreach(ASpell spell in sb.spells.Values){
          s._name = GUILayout.TextArea(s._name);
       }
 
    }
 }

Any help on this would be greatly appreciated! Thanks in advance