To export a prefab 3D model, open the game engine (e.g., Unity, Unreal) where the prefab is stored, select the prefab, and use the engine’s export feature (found in the right-click menu or asset settings).
Choose a compatible format (like FBX, OBJ, or GLB—good for cross-tool use) and adjust options (e.g., including materials, animations) to ensure the file works for your target use case (e.g., editing in Blender).
If you’re new to exporting, start with FBX—it’s widely supported, so you can easily open the exported prefab in most 3D software to verify its quality.