Serialized Properties

[strange crystal]

You need to use what are called SerializedObject and SerializedProperty to draw the field like you would see it in the editor normally.

When you draw and edit values using SerialzedObject/SerializedProperty it will also automatically support undo and dirty the object so it will be saved with the project

Also supports prefab overrides

You can look at the pinned messages in #↕️┃editor-extensions for more info on them