can a zeb ultimate pro web camera be used as a simple camera for photography offline?

Web cams are primarily made for streaming video over the internet, not good for serious photography tasks.

Most webcams offer the ability to take a single shot.  This would be part of its software which would also likely offer you the ability to choose a resolution.  You'd wouldn't want to use HD resolution which is only 2.1MP unless you're just posting to the web or sharing snapshots to friends and family.

Sure. Stick it on a notebook PC and get really crappy pictures but why why why.

Video web cameras typically have tiny sensors, with low resolution. Even if they can snap a still picture, they are not much good as a still camera. Cell phone cameras are different because they are designed to take good still pictures mainly, as well as video, so they are better than the web cams. For much better results, consider getting a DSLR or mirrorless cameras that cost a few hundred bucks at least or take your chance on a used one for a lot less money.