I whanna add a texture to a simple cube,as exemple.
I split the screen,a window in UV,another in 3D view.
In the UV i open a random image.
In 3D view i go edit mode i unwrap the cube.
>Now if i go to texture mode i have my cube textured with the respective image.
I save it as a .nif file,but when i open the saved .nif file,i can see my cube,but without any texture.
Can anyone help me with this?

.nif file? Never heard of that one…

You’ve missed out a fundamental step. You have not added a material to your object and added the texture to this material mapped to the objects UVs. Any exporter will therefore not know about any textures that your object uses…

I added a material,but i still dont see any texture when i open it with NifSkope
I followed all the steps from this tutorial>http://www.youtube.com/watch?v=k4pr3J45ESo