Export to .glb or .glTF formats: how?

Hi folks, I read here https://help.solidworks.com/2021/english/SolidWorks/sldworks/t_export_using_extended_reality.htm?format=P&value=

that my SWX 2021 can exports .glb or .glTF formats 

... but i can't find the way

I got "Save as" but dont see nothing else of what the help page explain ...

What's i wrong? Could you help me?