You don't train GPTs, you basically give it a few files and it can "decide" through embeddings, which files (or parts of files) are relevant for your question/query/prompt.
I asked it what the knowledge base provided consists of:
> Understood. My knowledge base consists of comprehensive and detailed documentation related to the Godot game engine. This includes, but is not limited to:
> 1. *General Overview and Features of Godot*: Information about the engine's capabilities, architecture, and general use cases.
2. *Programming in Godot*: Guidance on scripting, including GDScript, C#, and visual scripting.
3. *Scene and Node System*: Details on how Godot's scene and node architecture works.
4. *2D and 3D Development*: Specifics on creating and managing both 2D and 3D games.
5. *User Interface Design*: Information on designing UIs within the Godot engine.
6. *Animation and Sound*: Details on implementing animations and sound in games.
7. *Physics and Collisions*: Information on physics engines and collision detection.
8. *Optimization and Performance*: Best practices for optimizing game performance.
9. *Exporting and Publishing Games*: Steps and considerations for exporting games to various platforms.
> If your question relates to any of these areas or anything specific to the Godot engine, feel free to ask!