Regarding 2/, you need to use the loaders package to be able to load gltf/glb files in Babylon.
Regarding 3/, maybe other people will know if there are other assets, but it’s difficult to create assets with MSFT_lod as there are not many tools that support it…
Note: I have moved your post in “Questions” as it is more appropriate than “Feature requests”.
Also in the future please remember to state your questions in English Using a translator is fine but remember the forum is a global place so we have to mantain English as a base language for everyone to communicate
@qkrxotn7287, there is no support in the Max/Maya exporter for the LOD extension unfortunately. We have slowed investment on the exporters for now so it won’t be supported in the near future either. It seems like @labris’s point about Blender may be your best bet, especially if you are just using Maya or Max as a conversion environment and not tied to an art pipeline using those packages.