Importing .fbx and other files creates white model with no textures

Hello, I’m using cycles render. I’ve been trying to use the website to import models into my blender project, however I never get them to show up with textures or colors at all.
.fbx and .obj files will appear correctly, but all white without any type of color or texture

The latest one has been:
This one contains also a .blend file and no textures. Upon opening the .blend file, I can see that the colors are there as they should, but importing the .fbx file into another blender project, the model is all white.
Why is this, and how could I fix it?

you need to create new shaders manualy. fbx import does not convert shaders for you. it always creates some crazy shader nodes in my experience. But with cycles “principled bsdf” shader it is relatively easy to create the same result like your squid model if the textures are good.