How to import 3D object from imported json file

I couldn’t see the documentation regarding this. I need to upload an 3D object into the threejs scene. Since It is being huge in size (35 mb) . I decide to move some other way to perform this. I have seen these following two examples as per my need


I tried to understand which type of 3D object is loaded using the developer tools, While seeing it, these two applications having small size files only, But I couldn’t find the exact 3D object. I have seen only some json files contains the animation, materials, matrix etc… So I am trying to follow the same thing in my application to. For this, I refer so many documentations. Still I couldn’t find, how to do this. ?