I am new to Rhino and trying to edit a .obj file that I downloaded from TurboSquid. I have tried exploding the object but it is still not editable. I am able to select the object, but when I put in the command RoundHole and attempt to Select target surface, I am unable to select it. And it is the same with all other editing commands.
To edit a polygonal mesh you’ll need to use mostly mesh commands in Rhino. You can use the Mesh drop down menu to explore these commands or type Mesh and read through the autocomplete list of commands that include the word mesh.
Rhino is first and foremost a NURBS modeler but can work with meshes (obj and stl are common mesh formats) using the mesh specific commands.