SaveLoad

class A{
  enum ObjectMeshType{SQUARE, SPHERE}

  public ObjectMeshType CurrentType;
  public MeshFilter MeshFilter;
  void Save(){
    ASaveLoadStruct structToSave = new ASaveLoadStruct();
    structToSave.Type = CurrentType;
    string FormattedJson = JsonUtility.ToJson(structToSave);
    File.WriteAllText(path, FormattedJson);
  }
  void Load(){
    string SavedJson = File.ReadAllText(path); 
    ASaveLoadStruct structFromSave = JsonUtility.FromJson<SavedJson>();
    this.CurrentType = structFromSave.Type;
    InitializeAfterLoad();
  }

  void InitializeAfterLoad(){
    if(CurrentType == ObjectMeshType.SQUARE){
      MeshFilter.mesh = SquareMesh;
    }
    if(CurrentType == ObjectMeshType.SPHERE){
      MeshFilter.mesh = SphereMesh;
    }
  }
  [Serializable]
  public struct ASaveLoadStruct{
    public enum Type;
  }
}