Need help for a texture

Hello all, i have finally found a texture of imperfect cell ( DBZ ) but this is in a format .obj and .mtl, i don’t now how to adapt it to gmod and i am a newbie ( i don’t know 3d manipulation ), if a guy can convert it and upload thank you.

link : http://tf3dm.com/3d-model/cell-24496.html

Thanks you if you help me.

Mygale3124