problem when I have to add textures!

hey guys! when i choose “add textures” (terrain, grass, ecc…) the list of textures show only 6 assets: “grind”, “joystick thumb”, “skybox”, “thumb area left”, “thumb area right”, and “default-particle”! i can choose only this 6 assets! Help me D:
thanks!
ps: sorry for the english xDD

You need to add a texture to your assets folder. Try dragging one into the “Project” window. Or when selecting the texture, just drag it from the project pane (once you have dragged it in from where else it is) onto the object.