how import a 3d model by script?

hello. I need import a 3d model (.fbx or obj) to the scene from an outside folder. So do you have any workaround ?

Nope. Unity compiles assets into a custom internal format, and that’s all it loads at runtime. If you want to import raw models at runtime, you’ll have to write a custom importer. The good news is that there are lots of samples online if you search.