How to add render able Texture in Unity 3d for iOS

I am new bee in unity3d. I want to render an image on texture w$$anonymous$$ch should be stuck at one point, not stuck with Camera. I don't know how to accomplish t$$anonymous$$s task because I started unity a week ago but I want to do t$$anonymous$$s task as soon as possible. Kindly Help me on that. T$$anonymous$$s will be great for me. Thanks in advance.